Projects 57 Chevy 2 door conversion pics/build thread

I'm finishing up a '57 Chevy build and I took a lot of reference photos for the 2 door conversion so I thought I'd make up a build thread for it. Some of the pics are pretty blurry/poor and I neglected to take pics of a lot of other aspects of the build but it might be useful for someone in the future converting a 55-56-57 Chevy 4 door sedan into a 2 door sedan so I'm going to post everything I've got.

This was the starting point, purchased (and photographed) about 15 years ago from a Rawhide Boy's Ranch charity auction for $300. It was customized by some high schoolers I'm guessing in the late 70's, with orange fur on the door panels, shaved hood emblems and some pinstriping, bondo'd closed back doors with shaved rear door handles and 2 door Belair quarter panel inserts, air shocks, red velour back seat upholstery and some poorly installed '71 Challenger bucket seats.

 

First thing I did was pull the bucket seats and sell them on eBay, I got enough to cover the cost of the car and the title so the car was essentially free!

 

It had a 235/Powerglide in it, which I was able to get running. I swapped some Fenton Hawk wheels onto it, blacked out the rear door pillar, replaced the gas tank and had a bunch of brake and maintenance work done, and drove it around like this for the next 2 summers. The alignment was terrible and my replacement tires were questionable, but I was 24 and had a '57 Chevy and I felt like I was on top of the world.

At just the right angle, with the pillar blacked out, it almost looked like a proper 2 door sedan. From the side, it was super obviously not, but I enjoyed it anyway. The white paint was already falling off in big chunks, and that would continue at a much more rapid pace in the future.

 

Then, as any foolish young person would do, I decided it needed to have a V8 in it, so I bought a '56 265, and a friend of mine was going through it to prep it for a swap. Also, I was able to buy a whole front suspension with new bushings in it from a guy who was putting a different frame stub on his '57, so the rebuilt A arms got swapped onto my car, and the 6 cylinder got pulled out.

Then the project stalled, and it sat, for about 12 years. The tires had all gone flat, the paint flaked off, and mice chewed up what was left of the headliner. It was in my buddy's driveway that whole time, and another friend of mine begged me to sell it to him, so I finally gave in and sold it.

2 weeks later, it had a newer V8/TH350 swapped in, and he asked me if I wanted to buy it back. He had agreed to pay a guy to do the engine swap, it was finished and he didn't have the money to pay the bill. A trade deal was struck for the car, I paid the bill, and it came back to my shop, ready for the proper 2 door conversion I had always planned to give it.

EDIT Recently acquired this picture of the car right before I started cutting into it. This was during the 2 week period before I bought it back, one of the guys who had it took this so I'm adding it in here.

 

Anxiously looking for more please.

 

Squablow.......the master of 4 door to 2 door conversions... is back with another installment. Bring it on. I love these threads.

 

I really only started taking pictures when I tore into the 2 door conversion. I had neglected to take good reference photos when I did my dad's '56 Chevy, which you can see here.

https://www.jalopyjournal.com/forum/threads/56-chevy-2-door-conversion-build-thread.753008/

I knew when I did it again, I'd take more detailed pictures, and do this one a bit differently.

I started by cutting up some donor cars. Not to worry, they were extremely rotted, to the point the roof skins could be peeled off. The orange '55 pieces I ended up using, the green '56 pieces are stashed for future use. The '55 already had no frame, the dash cut out through the firewall, and half of the LH rear quarter panel missing, it wasn't fixable. It's getting really hard to find 55-56-57 2 door sedan donor cars in junkyards, especially where yard owners will allow you to cut them up, so I'm stashing whatever I can find.

 

Just so you don't think I cut up a cherry car, have a look at the rot in the rear door jambs. The holes reach almost all the way up to the door strikers, and they had already been gooped up 40 years ago.

 

With rot like that, the 2 door conversion is almost easier than keeping it a 4 door, since all of that area gets eliminated anyway. It would have been a difficult fix.

The first step was to replace all of the inner rockers, and several of the floor supports which were also junk. The majority of the floor pan was quite nice, which is surprising. I didn't take many pictures of this process.

One thing I did learn though, it's easier to cut out the floor above a bad body brace, and then cut the brace out from the top, and re-weld it in from above. The body stayed on the frame for all of this, which would have made welding from the underside more difficult. Once the braces were welded into the new inner rockers, it was easy to make a patch panel for the flat floor above, including holes I could weld through to the new braces, tying them together similar to the factory spot welds.

 

While I was doing this, I had to extract a broken off seat bolt from the floor, since I had an original seat frame I wanted to use. It took 8 tries to weld nuts onto the broken off stud and turn it out. I was so proud when I actually got the bolt out, I had to take a picture of all of the attempts.

 

thank you for being honest.

 

At this point, the inner rockers and body braces are all welded in solid, so I'm ready to start cutting into the body.

Since this is an ultra budget build, I really didn't want to pull the rear window out, because I'd have to replace the gasket. I was also leaving as much old paint intact as I could, since I'm not going to paint it any time soon. I tried to do things so that if/when I ever do decide to paint it, I'm not undoing old work. I just don't have the time or budget for a paint job right now.

Here's a better look at the rot in the old back door jamb. You can see where some former body man had made some stainless patch panels for the rockers. I left them in place for the time being, as a reference. They already had a bow in them, but I figured if the bow tightened up, or got bigger, I'd know the body was moving around.



Another view



And the first cut, eliminating all of the jamb. These pics get kinda blurry and poorly lit. They were taken for my own reference, but I wish they were better quality.



Second cut is on the inside, this little triangle of metal below the old quarter window has to come out to make room for the 2 door sedan inner panel that will hold the quarter window regulators.

 

On the 4 door, the back door jamb acts as the front of the rear wheel house, which is the reason they rot so badly in the rear jamb, and since that is eliminated, a new piece needs to be installed.

On my dad's 56, I just made new pieces, but my '55 donor had some vestiges of the original wheel wells still in it, with the rubber gasket still on it, so I scraped it clean, trimmed off the rotted part, and welded it into place.





There were some big gaps to fill, some from rot in the '57 body and some from rot in the donor piece, so I filled in the gaps with new steel.



Here you can see where the new arch is exposed on the side. What's left of the old quarter panel and rocker is a great reference to see where the big rubber gasket on the inner fender should land.

 

Now attention turns to prepping the donor pieces. The first cut is removing this inner panel, where the headliner bows go. This piece needs to be cut out of the way to access the areas that will be spot welded into the roof, but it gets reused in the end, so it needs to be cut out carefully. A row of spot welds gets drilled out at the top lip, and a solid cut through at the bottom to remove it will get welded back up once it's in place.



On the outside, the old drip rail and remaining bit of roof skin gets cut off.


And this section, formerly trapped between the old roof skin and the inner panel that was just saved, gets removed and eliminated. The top of the donor section should be smooth, just as shown here.

 

Now cuts get made into the roof skin of the car.

First, the skin of the top of the old rear door opening gets peeled away.



Then the inner structure where the headliner rods go, gets removed by drilling out spot welds. This also is eliminated from the car, to be replaced by the section that was removed but saved from the donor car.


The inside of the roof should look like this now. This structure must never be removed or cut into, it includes the drip rail and cutting into it will make the roof skin unsupported.



A bit more trimming gets that old inner skin totally removed, tight up to the underside of the drip rail.

 

The original B pillar/rear door post gets cut out completely, so the proper length 2 door sedan door can be hung. Getting the gaps right against the roof and rocker panel is important, since there's no B post to line it up to yet. Helps to have the front fenders in place and aligned as an extra reference point. Since the old front doors had good lines on this car when I took it apart, I left the front fenders untouched.

With doors hung, the donor sections can be cut down to fill in the big missing piece. Since my donor was so rotted, a large area of the quarter panel skin was removed, that I'll replace later. Here it is on first fitment. Getting the cut in just the right place is pretty important. No special steps, just a lot of careful cutting.




I overlapped the quarter panel sections so I could mark them and get a very accurate cut. The trimming of the pillar at the top of the window opening was just trial and error, take a tiny bit off, fit it, take a tiny bit more off, fit it again, until they matched up nicely.

 

I neglected to take good pictures of how the upper roof sections go back together, but I have good pics of that from my dad's '56 build, so I'll insert them here. Basically, the smooth upper area from the last picture in post number 14 gets holes drilled in it, in the original spot weld areas. That part tucks up into the roof, behind the drip rail, against the flat area exposed in post #15. Clamped tight, the holes are welded up, replicating the original spot welded area done at the factory. Should look something like this.



The piece I'm holding in my hand in those pics, is the piece that was saved from the donor car, in the first picture of post #14, now sandblasted and ready to weld back in.

That's the reason it was removed, to give access to this area that needs to be welded behind it. Now it can be welded back into place, along the lower cut line, and along the top where the old spot welds were cut out (note the holes along the top inside the car, that's where this will attach at the top.)

 

This is a picture of the inside of the inner panel that holds the window regulator. This whole section stays attached to the donor B pillar and should go into the car in one piece, getting welded to the wheel house and the ends of the package tray. I neglected to get any good pictures of this during the conversion, although you can see it in place in post 16. This one was cut out of a donor that already lost it's roof, so it wasn't suitable as a conversion donor, but I grabbed this just for the regulator parts, and took a picture to make it easier for me to figure out how to reassemble the quarter windows.

 

I ended up taking the skins off of the old 4 door back doors to fill in the big hole in the quarter panels, along with a section of rocker/lower quarter I made to replace the stainless steel patch panels shown above (hard to see in this pic, my shop is pretty cramped). Here's the door skin, tacked into place. It had the right shape and it was there, so I used it.

 

My pictures really slack off after this, I hadn't planned to make a build thread but I wish I would have, so much happens between this last picture and today. The brown 2 door sedan doors both got replacement bottoms, pieced together using bits of the old 4 door doors and the bottom of a smashed but solid '56 Pontiac 2 door hardtop door I found.

I had planned on leaving the doors brown and just putting some primer on the welded seams on the quarters once it was all welded solid and dressed, but it looked really stupid that way. So I painted the doors to match the rest of the body as close as I could get it without spending too much time on it, and I touched up the welded seams in the quarters, also to match.

Here's the first stages of paint blending.

 

The only real rust on the car is the left front fender, which if I ever decide to strip the car and repaint it, I would just replace. It looks OK for now but it's got pinholes in it and it's heavily patched, in the dogleg, around the headlight area, where the bumper wraps around, and at the top. That, and the panel below the trunk lid would need to be replaced.

The rest of the car has so much paint built up on it that it's actually quite solid.

 

In between then and now, a whole lot more work got done that I failed to document.

Windows went in (all used junkyard salvaged glass) but with new felt sweeps and channels.

I'd been buying and saving 2 door specific moldings, almost all used ones, along with good used bumper pieces and chrome bits. These were installed, along with long upper fin moldings from a Belair.

The inside of the roof got sandblasted to get rid of some bad mouse smell and some mouse rot of the roof got repaired.

An original '57 split bench got a ton of time spent on it, rebuilding the frame with replacement springs and a fair amount of welding on the frame itself to repair rot, then it and a 2 door rear seat got recovered with an old aftermarket slip cover set (not glamorous, but it works).

The used red carpet from my dad's 57 210 2 door hardtop went in over some sound deadener, along with a used set of door panels I got on Facebook Marketplace really cheap.

The engine install got totally reworked, with a different driveshaft, trans side mounts added in from EJGloss, and lots of horrible butcher work redone. Half of the bellhousing bolts were missing, the torque converter was held in by the wrong bolts, the shifter linkage was cobbled and needed to be replaced, along with the trans cooler lines, throttle linkage, and some sloppy wiring.

My buddy John helped sort out the mechanical stuff, and he checked over everything that had been touched, which is good, because a lot was wrong. I made up new exhaust out of scrap pieces, which turned out good, along with some chrome pipe ends I got from Bob Klessig's estate.

Some other HAMB members walked me through the proper wiring of the alternator and distributor, which was great advice and both worked on the first try, after following their instructions.

This past Friday was the first time I drove it in almost 15 years. Didn't go far, maybe 100 feet in the parking lot, but it was the first time it had been out of the garage as a 2 door.

 

Thanks for posting this. I wish I had this much detailed info before my 56 was done. You were nice enough to help tho!

 

It still needs an alignment, I have new rear leaf springs for it, and the rear tires are pretty weather checked and will be replaced. I also am working out a better transmission dipstick/tube setup for it.

After hearing it start for the first time, the engine ran so smooth, it was unreal. But then the throttle seemed to stick open at part throttle for no apparent reason, so the carb had to come off to investigate. It needed to come off anyway, as the studs for the carb were way too short.

Check out the carb studs with the nuts removed. Like, maybe 1 thread to catch on! Who does that?




I was worried the carb would need to be rebuilt, but once it was off, the culprit was clear. A chunk of leaf had gotten sucked into it, holding the throttle plate open a bit. I put an air cleaner on this engine as soon as I got it, but when I picked it up it had none. That leaf must have laid in wait over a year where it couldn't be seen, just to hold up the throttle plates on me after the first time starting.




After a good thorough blast with carb cleaner, it was reinstalled with correct studs and ran great again. The studs are a perfect example of the kind of workmanship this engine install had. Everything was suspect, and most everything had to be redone.

 

One thing I can add is the four door back seat can be modified to appear as a two door seat. The back rest is the same only the bottom is different. Every where i looked they were pricey, so i striped mine down to the springs and started snipping wires. All that needs to be done is to square off the front corners. Some careful tweaking and some wire from a scrap seat it was easy to recreate the corners. Mine has upholstery shop covers and looks great but if you want to use reproduction covers you might need to compare to a real 2dr seat.

 

Here's a pic of the passenger side from yesterday, now with the seats installed. I cleaned all the dirt and embedded grime and rust stains off of the paint and put some wax on it, that'll be good enough for beater status. The white/red/pink combo is kinda ugly, and after being cleaned, it's really bright. I like old paint, but I wish it was all one color of old paint. It is what it is for now.

It's probably a car deserving of nice paint in the future, but for now, it's multiple layers of old paint will keep it from getting rusty. I took great care in painting and sealing/undercoating the underside, it's pretty clean underneath.

 

That's all I've got. The replacement rear tires will be a bit taller, haven't decided if they'll just be plain blackwall or redlines like the front. I don't plan on whitewalls in the rear again though, those are just rollers. The new leaf springs should help get the rear up a bit, although the car still has the Gabriel Hijackers in it that were there since the 70's, which still hold air. Still has the Palatine High School parking lot sticker in the rear window, too.

 

I really appreciate guys like you and other HAMB guys that take on what seems impossible projects to the end. Thank you for posting. Impressive.

 

I did the same thing on a Mopar 2 door conversion, squared the bottom of the 4 door seat frame off, and it did turn out nice. The uppers are all the same on the Chevy sedans, in fact, the one in my car now might be the original upper, I don't remember. But I had an OG 2 door sedan lower to use, which was nice. I wouldn't hesitate to modify a 4 door seat bottom if that's all I had available.

 

Man, that turned out awesome! I would have been tempted to make it a 3-door though.