The 100 examples rule is equally flawed, given that the of various full sized Marcos models prior to the 1980's reincarnation, out of 13 major (production) variants, only 4 exceeded 100 units and 7 had less than 50 (plus two or three well known prototypes that I haven't even counted). Are they still classics? Of course they are. The ex-Jackie Stewart "Ugly Duckling" was one of just 9 built, but it was later raced successfully by Jem Marsh in UK Historic events.

Even when the models where numbers were higher, it is doubtful that 100 were ever identical, given the various options on offer.

Most were never homologated in period anyway making Schedule K a bit of a mission. I investigated it briefly at one stage and decided that there was no point whatever given that I can race the car anyway.

Fair call Dale, but I think most classic/historic people would prefer it went via a panel of people with sufficient knowledge and interest who at least understand why. Putting the option of a definition or ruling to one person is back into small black moustache territory!