[VegasDelta]

That was probably the original TH-300 trans that was used in Buick, Olds & Pontiac cars. It's not the same as a powerglide, which was a Chev trans. It was used w/the stock 330 & 6 cyl engines of that time. There should be no problem with it standing up to any small block. A 3 or 4 spd auto will get you a little better fuel economy & will keep your engine from winding out as much. A 4spd muncie will need a clutch pedal & linkage, different brake pedal, a bell housing & a clutch assembly. You'll also probably have to have the end of the crank drilled to accept the pilot bearing, unless your engine had a manual trans from the factory.