Note: I owned numerous muscle cars from the 60's and early 70's, and none of my GTO's, Roadrunners, Fury's, mustangs , chevelle SS or lincoln's had mph/kph stamed on speedometer cluster in dash or dual speed indicator numbers.. though i have seen a couple 1970 challengers with a 150 speedometer with mph under odometer . It was not common manufacturer practice 50 years ago to incur the extra manufacturing cost, since all speed limit signs were posted in MPH, and there were not s lot of imported cars being driven in America back then like there are today.