I did it. Figured out what was wrong with the 3rd brake light. Not sure how to fix it permanently, but it works for now. LOL I took a jumper box and clamped screwdrivers to it, then touched the studs on the tailgate. The light lit up, so that told me bulbs were good and wiring to through tailgate was good. Then I rigged the pedal to be depressed so I could go back and use a test light to see if the other studs had power. Yep, all was good there.
I was thinking that because my tailgate doesn't seem to shut correctly, it wasn't getting full contact. So I tried pushing on the tailgate and even though it did go in a little, still no brake light. I tried to twist the studs in the body, in hopes to unthread them a bit, but that didn't seem to do anything. I ended up pull out the ones on the tailgate a little. Now when it is shut, it comes on. Just don't know for how long. Anyone have a fix for this?
Here is the 3rd brake light lit up. I think I will order some Matte vinyl and remake it though, I'm not thrilled with the gloss look.
View attachment 72708
The tailgate fit can be adjusted with the latch strike pin on the left side of the body and a torx bit.