I know people who "back in the day" tried to order high horse camaros with SS delete trim, but were unable to. And obviously those dealers were not well enough connected to know how to order a COPO.
The closest thing to an SS with high po performance, but a non SS in a nova was an L 79, but that ended in 68.
Interesting. Either it's something most of us have never come across before, or someones got their stories tangled.
I tend to agree with Joe, in that I'd like to see some paperwork.
Maybe this is one of those cars that had the motor blown up almost immediately, and had it upgraded at the dealership to a L78 for a few bucks more. Then local legend made it a "factory" built car.