Not sure your intended use after this car is done. Trailer queen? Gears don't matter. If you actually intend to do any substantial "fun" driving at all I can promise that you are going to HATE 2.73 gears behind a 400 HO 4 speed. That is a drastic mismatch that will have truly dismal and inconsistent holeshot from a standing start unless you consistently and completely SMOKE your clutch every time you take off.
Agree you might as well drive it first and get an idea of what you might want. But starting thinking right now, because you will absolutely want different gears in this car unless you are truly gonna granny-drive it.