[COPO]

I think w/out factory paperwork, you'll have a hard time telling what engine is original to the car. A couple of clues for a 375 hp car would be the tag on the passenger side of the radiator (assuming it is still there) and a single 3/8" fuel line coming from the fuel tank. If is has a 5/16" line and a return line then it was not originally a 375 hp car. Finally, even if you are reasonably sure it is an original 375 hp car, I wouldn't attach much of a premium to it as you will very likely have trouble when it's time to sell. That's why cars w/factory paperwork bring the $$'s.