while i see your point, figure that the 6.1L has proven to dyno closer to 460 than to 425...so if you take the real horsepower, it gives you a lb per hp of around 9.04lbs per hp...a 2004 cobra (terminator) has a lb/hp of around 9.34, and thats a pretty quick car...
and some extra weight doesnt scare me any...almost EVERY car that i run against in the mirada is lighter...its just less strain on their trailers right after the race...