I'm not sure of the specifics because this tranny is for a friend's car and he is handling aquiring the tranny. There was a problem with the counter rotating shaft not fitting in the case because of the different size over stock. I think, IIRC, that they had to actually machine all the cases to make everything fit and then do some testing.....but don't hold me to any specifics because I am not really in the loop on this one. I am simply waiting for the tranny to help him get it installed so we can go back to the trakc for testing.
The TKO 500 is supposedly fine and has shipped from what I have heard but the TK) 600 is still in limbo and the only suggestion I have is to call Tremec directly.....if they will give you a straigth answer.