Many factory vehicles, particularly those with rear-wheel drive, feature an offset pinion shaft. This means the centerline of the pinion gear is not centered in the differential housing, but rather shifted to the passenger side. The offset is a common practice in domestic vehicles from Ford, GM, and Chrysler for various reasons, including engine and transmission placement, steering column fitment, and maximizing cabin space.
We are using the rails we have , so I am working on that. The string is within a heavy 1/16 th from one end to the other. So this looks to be a good start.
I spent some time cleaning up the shop and pulled another string down the right side. All is good, both sides are within a heavy 16th of an inch front to rear. Ignore all the temporary crossmembers , hopefully I can keep things straight when I put the heat to it . As a added bonus the cab is dead even on both sides, all though it is hard to see that in the photos.
I have not found a lot of info on Truck arm installation methods. I do have some friends I will call on as I get ready to build the crossmember. I came across this photo on the web for what it is worth. I was in a shop the other day but the cars sit so low that was of no help because you can't see up under them. Here is the article https://www.hotrod.com/how-to/ctrp-0712-racing-driveshafts-101/
As for the t/a install... American Rodder did a nice article, iirc, on a t/a install, & the reason(s) to use one. ~1990->1996-ish? I looked at my available(whole) mags, & I don't have that issue. I stripped the article out years ago, but don't know which box it's in, nor where it is at the moment. Hopefully someone else can find it & get you a copy. *If* I do find it before you need it, I could text the pics to you. There was also an article(ad/editorial/"feature"/advertorial) from Street Rodder(?) by the HotRods from Hell???, but it didn't get too technical, iirc. There are 2 different oem length arms, depending on wheelbase, but they both converge about the same distance apart, just after/over/around the front u-joint. Factory crossmember was fairly stout, w/simple "U" brackets that were angled(& just riveted to the crossmember) to match the arms' angles off of the rear axle tubes. I have one in storage I could photograph & measure, iffen it'd help. Would need your ph# in a PM. Proper articulation requires it be as close to the u-joint as possible. Factory(chevy/gmc pu) used the ubiquitous steel-encased rubber bushing in the front of each arm, which gave good service & needed flexibility. If you want better, use Johnny-Joints from Currie(I think) for the off-road 4x4 guys. Late 40's(iirc) Buick was similar tech, but different bushings & mountings. Marcus...
Thanks for the offer Marcus, But I was at a shop yesterday and picked up the brackets I need for the front mounts and the saddles for the axle housing and got my questions answered.
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