This is a bump as well as a plea for an answer for you. I'm in the same postition with my 34 Ford. I have both a TH400 and a Muncie 4 speed. I really want to run the manual but need advice like you.
If I don't get something soon, I'm gonna take the easy way out and run the TH400. But that's not really a 'hot rodder's' way, now is it?