Hi guys, getting antsy to work on the MogRod, so I figured I'd start sorting out the wiring harness for things like lighting and such. However, the original harness is in sad shape and thus of no use as a reference. This has led to a question I'm hoping some of the classic +4 owners could answer for me...

On the rear lighting, the larger housings have a dual filament bulb while the small housings have a single filament bulb. I'm assuming, based on most vehicle lighting, that the dual filament bulb is used only for brake lights and 'running / night' lights, and the smaller housing's single filament bulb is only used for signaling?

Somewhat related to this.. what was done for a reverse light originally? If nothing was used, what lighting solutions have owners come up with to make other drivers aware that they're backing up?

Thanks as always!