With the original two bulb tail light you might have to mount a separate light to use as a turn signal. The problem with your housing is a bright bulb won't fit without bending the bracket the sockets mount to. I use a #81 6cp bulb for my tail light and a #1129 21cp bulb for the brake light. I believe originally a #63 3cp bulb was used for the tail light and the #81 was the brake light. As I mentioned the bracket must be bent some to use the #1129 because it's longer and won't clear the lens. I don't know what the 12v equivalent bulbs would be.
Well, it's using the original housing, and there are two small identical looking bulbs mounted vertically inside on a plate, that looks like it might be stock. However this truck does have working turn signals. All the wiring is currently ripped out, so unfortunately I can't just test it to see what is what. I'm just trying to figure out how to connect the new harness to the rear of the truck. The harness has wires for "tail" and turn signals", but nothing for "brake" (there is a wire labeled third brake light, but I don't have one so I just tucked that wire away). So based on Cletis' response, the turn signals and brake lights share a bulb, and the tail light has it's own bulb. I'm just curious how this actually works, does the bulb get less voltage for the turn signals and then more voltage for the brakes so they are brighter? I don't think it would shut off the brake lights so the turn signals can come on. How does it work when you use both the brakes and turn signals at the same time.
And inside a stock 1940 tail light housing, which of the two vertically mounted bulbs is which?
