My 1957 has 3:38 gears, with a Chevy 348 engine. Runs great in all conditions. For a while I had a 283 (one 4BBL), that also worked fine. Sounds like you have plenty of power to work with. I got my gears from Patrick's (it is a NAPCO truck.) I also installed a dual master cylinder with disc brakes up front because of the problems with the NAPCO brake parts (they are Studebaker). I'm very happy with that choice also.
don
