welcome aboard VMF Wally.
sounds like youre on the right track with your research.
if it wasent a Spec order paint code it could just very well be a mis stamp.
if youre a brave sole post the vin and maybe someone out there had the car or knows something.
also do an email blast of all the stang clubs you can find online.
i had a club memeber get lucky about 10 yrs ago and found a PO that way that supplied him with a lot of lost goodies. belive it or not theyre still in touch and became pen pals so to speak.
you can also try for a Ford 999 report. They used to be free but now i think it may cost a few pennies.
1970 Mach 1 San Jose built Dec 23 1969. Marti says 1 of 7. Purchased in 1987. Original family owner of the powertrain 351C 2v FMX.
1993 GT 11,000 miles, Built 2-12-93 Auto, 3:27 Axle, cloth, sunroof. Untouched except for rubber and battery, Purchased new 8-3-93. still has the factory windshield fluid and new car smell.