I'm still working on getting my electroplating setup put together and waiting for a couple of supply items. In the meantime, I'll keep working on various parts of the M37.
My M37 was never equipped with backup lights, and I don't think I'd ever have occasion to use the small "blackout marker light" at the right rear of the vehicle, so I decided to keep the marker light, but convert it to a backup light. Re-purposing the old blackout marker light would maintain the original outward appearance of the vehicle and make it easier and safer to back up at night. I already had an old beat-up marker light, but I found a marker light in excellent condition on eBay for a decent price.
First, I removed the blackout marker lens parts from the light:
Then I cut out a piece of a backup light lens from another vehicle and installed it in the blackout marker light 'door' in place of the above pieces.
I cleaned and painted the body of the light Marine Corps green outside and white inside to reflect more light.
I installed a bright white 24V LED lamp, sized so that the end of the lamp is at the approximate center of the new lens.
Here's the finished backup light, ready to install (although that may not happen for a while yet). Note: There is a piece of 1/16" flat, clear polycarbonate in front of the lens, but it isn't apparent in the photo below. I installed the flat piece to make it easier to seal the lens and to keep the front of the lens clean.
Since the M37 never had a backup light, I'll have to make a minor wiring modification. I suppose I could probably design some kind of gearshift-related linkage for a backup light switch, but I might just end up installing a manually operated switch on the dashboard, in which case the switch would have a pilot light to remind me to turn off the backup light after backing up.