Remove all of it and the trans will go first then when you get a beefed up trans or put vette servos in the rear end will explode. Me I'd remove all of it and replace the trans see the 4l80 post on the front page. Then replace the rear end. Then add a huge turbo then when you scatter the motor and need another buy an LSX454 and get another turbo since metal from the scattered engine killed the original. Then buy some brakes you'll need them.