Kurt,

Sounds like a chaffed (SP) wire somewhere. grounding out and blowing the light.

You might try cutting the wires to the offending light and splicing into the wires of the other light. Leave enough length of the wires so you can hook them back up correctly later if you need to.

You can take to an automotive electrician and they can try to smoke the wires to find the bad one. I.E. over amp/power the wires until the bad part starts to smoke a bit. Seen it done before on a machine we had at a shop that I worked at. That is the last resort though.