Better Shifting Mopars

The reason for the rebuild is that I'm doing a 4-speed swap from an automatic and the tranny is still on the bench (actually on the floor). Seller told me that he think it was rebuild but he is not sure as it came with a new overhaul kit when he bought it.
I won't start the swap till fall so there is plenty of time to go through the tranny.
What I don't have is a new counter shaft but I have access to a lathe so I might just get one made.