Transmission related questions

[73c20]

I have a 1973 CHevy C20 with a 350 V8 and th400 transmission and i would like to swap to a SM465 4-speed.

1) what size flywheel/clutch were used (and what is the tooth count)?
2) what is the spline count on the crankshaft output shaft?
3) does anyone know any company that makes a performance shifter for the SM465, or would i have to stick with stock?
4) would a different crossmember be needed?