Not sure an "original" had a right light. Several on the internet with no right light.
I like to figure out electrical/mechanical issues but not early truck experienced. I try to use stovebolt and the internet to help me. I have exhausted my usefulness on this one. Unless Philippe wants to do a new socket thing.

Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn