The first two post were posted to another thread with slightly different focus. Thought I would put them in their own thread so that clarity and consistency could continue for both threads.
As mentioned starting back in the 80's Mustang coupe with red interior started being noticed with white headliners. At first we sort of ignored them, assuming that the headliners had been replaced. After we had seen about a half dozen examples, which we had identified as December 65 projected build date cars we took noticed.
Not sure of the reason other than a possible supply issue but just an oddity that stood out over the decades