Barn fresh find today, can you help me?

It's a 10,000 day calender system used by Chrysler for engine stamp numbers. Not sure when it started, but 3139 is March 2, 1970. The calender I have (Galen Govier white books version) shows July 1, 1967 as 1799 but doesn't show anything earlier. I guess you could figure it out. As is the Galen Govier way, anything made prior to then isn't worthy of documenting I guess.