Since A-Body 8 3/4 rear ends are getting hard to find, and prices have escalated, a lot of A-Body owners are swapping in B-Body and E-Body 8 3/4 rear ends.
If you get a B-Body 8 3/4 from a 62-70 car, the perches are only 1" wider than the stock A-Body width, which works out to 1/2 per side. There is enough play in the leaf spring bushings to squeeze these 8 3/4 rear ends without ANY modifications OTHER than having a rear rim with the correct offset. So an 8 3/4 from a 62-70 B-Body is a direct bolt in.
Since the Dana or 8 3/4 rear is from an E-Body at a MINIMUM you will need to move the perches as they are 3" wider than the A-Body perches, again you'll need make sure your rims have the correct offset for the wider rear end. You'll need more back spacing.
Obviously you could also have the rear end narrowed, but this is not necessary, although if you are also going to mini tub the rear, you'd need a wheel with A-LOT of back spacing, and some have found rims with that amount of back spacing to be difficult to get on and off the car. Some find it necessary to jack the car from the bumper to get the rear axle to hang down so they can get the rim mounted.
Hope this Helps,
Regards,
Joe Dokes
PS, Thanks Dfnsmn34, That is a handy chart to have.
