internally your TH-400 is identical to the GM version- all parts interchange- the bolt pattern on the front of the case is different and the output shaft is different. Other than that its the same. Advance, Novak, etc all sell adapters to mix and match- but if you are swapping in a GM engine- save the hassle of adapters (and the additional length) and use a GM TH400 case. Good luck, Luke
JEEP- Just Empty Each Pocket. Oh well- its just money. o||||o