Thanks Rich, I really don’t know for sure what year they started with but In 71 BTK ran a Challenger, so my guess is the Demon was a 72. They did convert the 72 to a 73 with the addition of fiberglass bumper as they were allowed in 73. They were painted white and the Dodge logos on the quarters changed to Independent, as Chrysler pulled a lot of support from teams. Do you have more information on dashboard? I know they had a standard rectangle dash and the Rally dash with round gages. The rectangle gage dash showed up in most of the google search I did. I did notice the straight vs. angled area above center the A/C vent, but I don’t know if that changed between years.