You will either have to move the springs in or the spring perches out. I have put B body housings in both the Cudas I've owned, as they are easy to find, and it gives you about 3/4" extra tire clearance on each side. I have gone the route of moving the spring perches in both times that I've done this swap. I believe there is about 1/2" difference on each side. It's my understanding that the Mopar Performance offset shackles and front spring hangers will set the springs in the right amount so that the B body housing is a bolt-in, but I have always gone the cheaper route of relocating the perches.