slick decision

I'm not GTX John, and I obviously can't answer for him, but I can tell what I did. I have a 62 Savoy with the stockrear axle location unfortunately biased to the front of the opening. When I replaced the stock springs with ss springs, I redrilled the front mounts to move the whole rearend back one inch.
I do NOT know if that solution would work on your A-body.