My new 65 has nothing at all in way of backup lights. I can buy replacement lights ok but have no clue as to how they worked in past.
Did they actually work when you put it in reverse? HA.
Is it worth pursuing? I was going to rig a manual switch to turn them on when I need them.

Vehicle inspection in Louisiana is strict. No sticker and you get nothing like plates, insurance etc. I simply told the guy they didn't have backup lights back then and he thought that was cool and gave me a sticker. I'm rolling!

O BLUE 65 stepside