1976 Dart - ignition switch

The order was always (starting fully counterclockwise): accessory-off-run-start. That is how your car was built. If yours differs, something's upfuсked. That order you describe (off-accessory-run-start) is common in Japanese and European cars, but not American ones. Sounds like your switch is badly hosed or someone's hacked in something that shouldn't be there.