Were those the wheels with eight bolts? I remember them from about 1962 or ‘63 when they were standard on a very limited edition of the Gran Prix that came with the 421. That model also had some aluminum body parts— at least the front fenders— to keep the weight down for drag racing. There was a kid in town who was a senior when I was a sophomore in H.S. who had one. It was quicker than about anything except my best friend’s older brother’s ‘61 Corvette with the 425 HP dual quad 409 that had a 4:88 posi rear with close ratio 4 speed. That car would only do about 110 in fourth gear at 7 grand but it would do it like RIGHT NOW.
It took me a few minutes to find them but you are definitely correct on the eight lug wheels.