1964 c10

[holden64']

Howdy, I have a 1964 c-10 longbed that I am currently in the process of going thru, recently took out what I believe was the original 283 and Saginaw 3 speed. Most likely putting a recently rebuilt 350 bored .40 over out of an mid 80s suburban in the place of the 283. I am wanting to also to put a 4 speed in place of the 3 speed. I have been looking at an m21 Muncie, but also looking at the 4 speed saginaws. Plan on this truck is much more of a daily driver and work then an show truck. Wondering if anyone has any opinions on an decent tranny for this thing.