on my 68 Dart I ran the a-body 8 3/4 with the large brake offset on the axles with green bearings which made the whole rear axle about 1/2" wider than stock..1/4" each side,IIRC

I ran 245/60/15 on 7" rim with a 4.5 backspace

fit just right and tire was centerd in the stock wheel tub

I did not have to roll the lip on the fender

was a 1/8"-1/4" clearance on the tire bulge and spring pack

just remember to figure in the tire bulge when measuring the rim/tire combo