demort71

Moparman390 is both right and wrong when he states that the fender tag does not show the sunroof option on it. He is also both wrong and right when he says the assembly line worker did not need to know if a car was to have a sunroof installed in it. OK, let me explain...

First the fender tag will not denote the M51 option on it per se (it won't say "M51" any where), but the tag does indicate that it had the option via the order number (no I don't mean the sequential number). The order number will have a letter in front of it and then digits after the letter. For 1970 it was a K and G for 71 (and probably thereafter). I doubt that it made any difference what the body style or model the car was, they probably all used the same letter in the order number.

The letter in the order number probably indicated the car was to have special handling on the assembly line. The K designation in the order number may have been used for (for example) 1970 Super Birds which were finished off-site. Anyone know about that?

Looking at the 1970 broadcast sheet (1969-F series sheet), you will not find a place on it that denotes the power sunroof option. On the 71 version you will.

The assembly line did need to know if the car was to have a sunroof. All power sunroofs in this period were installed by ASC or American Sunroof Corp., which had a production facility and national headquarters near the Hamtramck plant in suburban Detroit. Any Mopar that got a factory ordered power sunroof was produced at Hamtramck for this reason. The car was pulled from the assembly line when it was drive-able and almost finished and sent to ASC for installation of the sunroof. This process appears to have taken about two to three weeks, after which time the car was returned for Hamtramck for final processing, assembly and inspection before it was shipped out. A lot (but not all) sunroof cars will indicate one build date on their fender tags, but have a later build date on their original door VIN sticker because they were sent to ASC. The door VIN sticker was produced after the car came back to the plant. Rather than the door VIN sticker being printed out by a computer printer, these sunroof car's stickers appear to have been typed on an electric typewriter because the fonts are different than what you see on regular assembly line cars.

Now, it doesn't make any difference if a car was destined for California and we know there was an assembly plant there that made Challengers. If it had a sunroof and was destined for Cali, it was still made at Hamtramck. End of story. Same thing goes for Chargers destined for St. Louis!

The picture that Moparman 390 included with his reply certainly lookes like an ASC sunroof. This the way they all looked and were shaped when looking up at the cieling. Yours should look that way too. ASC used special parts and pieces in all of their Mopar installations.

I believe that ASC also installed all of the sunroofs in later 70s cars for Chrysler, including the manual units.