Evolution of Automotive A/C, Windshield Wipers, etc.
I love old Chryslers, but I think you had to buy a 1974 model or later before "Vent" was a part of the A/C equipped climate controls, so there was no "Vent" air coming through the dash vents, but the floor vents on the left & right sides w/ the louvers still had the levers you pull, so if you wanted "Vent air" you'd get it, but down below, wheras "Strato-Ventilation" would be dash-level air, as well as standard heat & defrost, but you would have to go to after-market for adding A/C...
Delay or Intermittent windshield wipers weren't available until '74, either; same for GM, but Ford had 'em as early as '72 or '73 (and see the movie, FLASH OF GENIUS for history on that, too!)...
-- Dave