Is there a big difference in physical size between the 2? I got a real nice 727 core that I was going to build for my 65 dart but if a 904 is a bit slimmer ill go that route just because of exhaust clearance etc. if not ill just build the 727.
904's are quite a bit slimmer, and a few inches shorter. IMO you definetly want a 904 in an early A. There's not much room there anyway. Sticking a big ole 727 in it will make life a PITA when working on it.
