8 1/4 swap questions

I don't know that's a pretty big jump in width, 3" on each side is quite a bit. I swapped an 8 3/4" in my '70 Duster that was from a 1967 B-body and IIRC it moved the wheels out maybe an inch (at most) on each side. Definitely needed extra backspace after that, my 275-60/15s would rub the outer fenders occasionally.

I guess what I'm saying is you *can* run that extra-wide rear end but you will definitely need some aftermarket wheels with lots of backspacing unless you want half the tire sticking out the side of the car lol. I'd suggest looking for an 8 1/4" out of a Jeep Cherokee or Liberty (those have disc brakes btw), I'm building one up to swap into my '88 5th Avenue (M-body) and the overall width is spot-on, all it needed was the spring perches relocated and the Jeep-style shock brackets removed since cars use shock plates instead. I picked up the entire Jeep XJ Cherokee 8 1/4" assembly with 3.55 gears for $100 from an off-roading buddy, Jeeps are all over the place here and used parts are a dime a dozen.