I can tell you not to buy from TCI I've had nothing but problems with 3 of theirs. I've had very good luck with California Performance Transmissions, hands down the best trans I've ever owned.
I have a factory built 4l60e. new clutches,servo,bands,sunshell,tricks to valve body,shift kit,and bunch other goodies a buddy did for me. Lucky for me he owns his own transmission shop and takes pride in his work! Oh also billet Yank stall converter.