[427.060]

I think the car had to be a COPO or modified by one of the high performance dealerships such as Yenko, Harrell, Gibbs and Baldwin. Most Chevy supercars were L-72 427 powered. The 1968 Gibbs Novas are one of the exceptions. If the engine package could be ordered as a RPO option it should not be concidered a supercar. There are plenty of very nice high performance cars like the LS-6 Chevelle, L-78 cars, Z-16 Chevelles and others that are super cars but would not be concidered a supercar because they were regular production cars.
James