Not sure where the gas tank was I guess I didn't pay that close attention to it. As for the t-case I think it was stock that way. The guy I might buy it from bought it from the original owner. But maybe when they switched the motor they kind of changed that all around too? Not sure why, but maybe? It has a 4spd manual in it right now. Is that a good tranny? I know where I can get a c-6 and switch it over to an auto.