Do any old timers remember seeing these on a 1971?

Locomotion said
Looking through the factory brochures, it does appear that those hubcaps started on 1972 Darts and continued through 1976.

Factory sales brochures.

Thanks for that link. Another website that has the same type of info is something I can never spell, LOLOL

https://www.hamtramck-historical.com/