It appears all the confusion is about the construction and connection of the buckets on the pre AD pickup. Here is a pic of all three components in question. The entrance from the truck body to the bucket has a disconnect that mounts inside the bucket as shown. The connector is a push and twist as seen in my pic still connected. Once disconnected the reflector (with its pigtail) is fully removable to be serviced or replaced. As you can see from lack of any insulation and snipped wires I cannot be of any help with “what goes where”but I’m not sure it’s important as long as both sides are the same and it functions properly. Light holder simply made a butt connection ilo this connector as he didn’t have nor could find leaving some excess wire bundled in the bucket just in case eliminating the fully removable pigtail connected reflector. No problem.
Larry Old man᠁Old truck᠁neither one goes very fast. All you need in life is TIME, PATIENCE and MONEY. If you are missing one component, you'll need an abundance of the others two.