A-12 means that your into date coded, nos, correct, details, far worse than any Corvette owner could ever dream of being, which is`t a bad thing. A-12, m-code, 69 1/2, h-wheels, oe bathtub aircleaner bases/lids, 054 radiators, fiberglass lift-off hoods, all = mega $$$ I`m not too old to remember when those cars were all about racing, fun, and wrenching. Today they have become so valuable that most lead pampered lives.