I used the 68 A-body 8 3/4 with a shackle/axle flip/flop tucking in 12x15 rims with a 29x15x15 M/T on my 88-440 truck.

A-body and truck share the same 43" perch centers on the leafs. was a bolt up deal after removing the rear shackle mount and replacing it with a front spring mount to flip shackle. axle bolt right on top of spring with A-body u-bolts/shock plates. I used truck shocks.

gives a nice drag stance, good ride/handling, still haul a 440/trans in the rear with no axle/frame contact.

I have a e-body 8 3/4 I going to use on my next truck.

you can fit a 10x15 rim with M/T 29x15x15 on a stock width truck/c-body housing with 7" backspace on rim and tub work.

the A-body 8 3/4 used a 12x15 with 4.5 backset

if I measured correctly the e-body 8 3/4 will allow 10x15 with a 5" BS

I also used a 70 mustang gas tank mounted in the rear frame rails 125$ fuel gauge works and 3/8 pick up tube.

LMK if you want some pics.