B body rear in an A body

Has anyone put a B body rear in an A? I know you move the perches in 1/2 inch on each side but what i'm wondering is will a set of stock rallye wheels cause me a problem via backspacing? The wheels are off of a 76' Aspen R/T. All your help and advice is appreciated

Floyd

oh yeah, rear is out of a 69' Roadrunner