I wouldn't touch it. You're looking at an excercise in futility. A gertrag 5-speed from a sunfire (or cavalier....the guy can't make up his mind on that) won't take the torque of a stock 3800, much less one running a 150 shot of Nitrous. Some excellent advice was offered here recently on the same trans swap idea "get a clutch that slips......BADLY". He'* going to be twice the rating of that trans. And he picked a clutch that wouldn't slip. Bad combination.
He painted his SC. This is even worse in that tiny engine bay, especially since he also used the stock Cav radiator.
It'* a fun idea, but the end result is inevitable. He should have used a 4T65E-HD, with modified halfshafts (shorter).