The Neoprene seal will work on most late 1955-62 engines as they do not use shims and the seal groove is more accurately machined.
Chevrolet even sold Neoprene seals as a replacement for these engines. There is the rare occasion where the seat groove is not concentric to the crank but that is rare.
I know Best Gasket includes a pin to keep the seal from spinning but I would take my chances on that. I do not use the pin.
