The post got my attention. I sold a 71 RR 340 AT in the early 80s here local. Guy that bought it passed away. He had painted it black at one point.
I lost track of the car and would love to find it.
Try a search on your car at www.hamtramck-historical.com They try to get build sheets , fender tags ect that are turned into them back with the cars they belong on.
Prob a long shot but worth a minute or two.