I had a midwest in my t/a..3600/2.0 str b/c I ahd 3.73's..if you have 3.42's thats a bigger gear than the stock 3.23's I would go around 3200 on a ls1, you will be happy, yank, TCI, or midwest is the way to go, if you can get a deal on a yank do it or the other ones will be cheaper, and try to get a 9 in if you can, I had no problems daily driving mine when I ahd it, jsut other stuff broke on it instead lol