Over on the Road Runner's Nest we got into a big discussion about the factory options on the Plymouth Satellite/Roadrunner line of the mid seventies, and a gentleman that worked at a Plymouth dealer in the seventies jumped in and solved an issue about factory options. It seems that Plymouth and Dodge both sent vehicles to dealers that were incomplete just to get them off the assembly line, sometimes without steering wheels, radios, and missing drive trains. It was up to the dealer to complete the package. It solved an issue with my 73 Roadrunner I owned in 1975 when I was eighteen. I bought it at a bank repo lot, and it came with an electric antenna, which wasn't an option on the Plymouth Satty line. It was a Mopar part of the day, but it was an option on the high ended Chrysler line, and I'm betting that's where it came from. It wasn't on the broadcast sheet. Young RR owners took issue with my assertion I bought it that way, it wasn't a viable Plymouth Satty option so it couldn't be original, even in 1975. It was a repo...the previous owner owned it for about....six months, and I bought it on the cheap.
It could be that the amber/clear lenses are in a similar situation. The trucks were received at dealer incomplete, and the parts department had to complete them with the parts on hand.
Just my 2 cents worth.