B body 8-1/4
I would imagine a B-body 8 1/4 would be the same length as a b-body 8 3/4, so that being said, I have a B-body 8 3/4 under my 68 barracuda. I moved the spring perches inward 1/2" each side, then I used a 17x8 inch rim with 5.75" of backspace. the wheels seem to be centered to me, it looks good.