Doyle , if I read your starting post correctly ,you have installed a Tr3 box that you have
not gone through. If it is a non OD box, promptly scrap it for a good Tr4/6 box.
If it is an OD, re-build it correctly and make sure the Laycock if in good shape.
It is a bad idea to install an untested tranny,leads to profanity and excessive drinking.
(and I said it with a straight face)
Mad dog