I am putting together a 67 convertible. When I bought it it had a 283 with a powerglide transmission. I was able to get a 400 CI Pontiac motor. I intend on using a Muncie 4 speed and have found one from a 70 Camaro. I have a pontiac bell housing. Are there any issues using a newer Muncie transmission that I should be aware of before I buy the transmission?
Also make sure you use a Pontiac throw out fork, Chevy is not the same. And many folks run into trouble by not having the right throw out bearing for their pressure plate. There are two different length bearings, for low and high diaphragm clutches.