The car was actually a gts not the gts-t. I went to school with him, was a crazy car.
I would definitely go for something like the ls2 or the likes. Alot of parts around for them and enough info on the motors. The only other option that I would have thought of would be the v8 rover alloy motor. It is quite light for an 8, but i don't know how you would go about getting parts. I know my tafe teacher put one in a suzuki mightyboy...you guys might have seen it at the hillclimbs or sprints...its a purple thing and has a supercharger on it. Was up for sale last time I checked.