Sharp lookin' truck! I'm jealous. If you look at my truck, you'll see why!
If you've got the correct bulbs in the correct places, then I've pretty much got nuthin'.
It sounds like a bad ground until you pull the other light bulb. It might still be a grounding issue.
Visually inspect your wires, clean up your grounds, and if necessary, export your grounds.
I have all of my grounds going up to the headlight ground screw on the inner fender. You could just as easily go to the seat riser or to a bolt on the block or transmission.
Good Luck!
