Technical 1937 flathead distribtor

I have a 35 ford with a 37 block. Im using the 35 heads intake and front cover off the original 35 engine. When i try to install the 37 distributor it wont seat all the way. Is there a difference in 35 and 37 covers? Ive noticed one more bolt hole on the distribtor thats not on the 35 cover. Seems like it should work though.

 

It should fit. Study the drive tab on the distributor first, it is slightly, almost invisibly, offset and can only go on the right way. If no go nohow, study everything for burrs or damage.
The 4 bolt holes have a slightly bizarre justification...85's used the same 3 holes as '32-36 distributor. V8 60, using the exact same distributor as 85, used the extra hole in place of one of the regular ones. Who knows what they were thinking.
More fun with obsolete junk: Scrutinize the rear of the distributor shaft...if it is stamped "68", a # introduced on a variant '36 ignitor, distributor is a '37-40. If it has an 11 back there, it is from a 1941, same distributor with a slightly faster advance curve.

 

Maybe this will help.

 

I may have found why this dist wont seat all the way. In the picture the casting is thicker on one side thus it isnt letting it slip in all the way. I intend to dremel away a bit of it. Im confused however that since this is a rebuilt dist how it ever fit? Unless the 37 - 42 cover has more clearance.

 

Before you Dremel anyhing, can you clarify exactly what you mean? You might be removing something important. You do understand the offset tang, don't you?

 

If you look at your picture, you'll notice the upper half of the tang with the stamped number is slightly larger than the lower half. The end of the camshaft is similarly offset. Line up the offset on the distributor and camshaft by eye and then slowly turn the rotor until you feel the two click into place and the distributor fits flush against the timing cover. Don't try to force it flush with the mounting bolts, or you'll break it. This is basically the procedure described in the attachment to my earlier post.

 

Yes the offset tang is seating ok. The dist almost fits in all the way but it rocks back and forth and i am not ready to bolt it in to force it. I think the circular opening on the cover isnt allowong that bulge in. The original dist fits fine.