If you are putting it behind your TT, you may want to think about a G-Force or Transzilla T-56....
I just got mine back fron G-Force. Besides the close ratio, hardened gears, I had them machine some threaded openings to attach hoses for a trans. pump. This pump moves the fluid from the back of the transmission (needed for the G's created by the turbo power) and moves the fluid back to the front. This is to prevent gears from running dry.
For a stock tranny, you can't beat Scharf...