Pretty sure NASCAR and NHRA had a minimum 500 production units, hence the '69 Charger "500" name as they had to build "500" of them. And there was an intent to only build "500" of each A12 6BBL Road Runners and A12 Six Pack Super Bees to meet NHRA'S production requirements (and then mess with NHRA on submitting specs as they felt a COPO Camaro with a 427 ZL1 that was allowed into to did have the documentation of "500" built or available at dealerships) quite funny and fun for the engineers at the time.

How many Hemi Darts were built, only 50? If so did it run in a production based class? That would make a difference.