Well, both...So I can have the 4 1/2 bolt pattern, and run the standard 17x8 with 5.72" backspace mustang style rim... The stock length A-Body axle will not work and I do not want to and will not use wheel spacers. IIRC, the B-Body axle is 2 5/8" longer than the A-Body axle. All I'd have to do is move the spring perches in 1/2" on each side...