Good suggestion, I reckon they need to have a cut-off year of say, 1975 and maybe just let special vehicles in as well.
By this I mean FPV, HSV, and later high interest cars only, like Vettes, Camaros, Mussies, Exotics, Limited Edition Specials and performance cars etc.
Its pretty ordinary when you are parked next to a stock VN C'dore at a "Show".