Joseph, I've got a 54 Chevy with Hydra-Matic. Getting ready to start the restoration. I was considering swapping out the trans but after further research and the input from the forum members here I'm going to keep it (thanks again to all who weighed in). A rebuild is about $3000 plus shipping to Gene at
http://www.restorationhydramatics.com. It isn't cheap but you might wind up with less $$ invested than with what you're thinking of doing. Plus, I hear they are a GREAT trans and really trouble free. Just my .02$ for what it's worth. Best of luck on your project. Would love to see some pics.