OK...I am now ready to ask for help (or read instructions if anyone has some). A few days ago the right tail light on my 63 fleetside stop working. The turn signal still worked, but no running light. Checked the obvious things (bulb, brohen wires, etc) but no joy. I'd read on this site that sometimes these old trucks have ground problems due to rust and corrosion behind the housing. I took it apart and cleaned all of surfaces neccessary to get a good ground and in the process found some very suspect wiring installed by the PO. I use "installed" as a very loose term. Lots of wires twisted together with electrical tape, etc. I ordered new tail light pigtails for both sides from ChevyDuty and replaced the wiring harness with all soldered connections. Now when I really have a problem. With the headlights off the turn signals work fine...when the headlights are on the right turn signal will blink, but there is some "winking" on the left side as well. The left turn signal doesn't work at all with the headlights on. The re-wire seemed pretty straight forward with only three wires (brown, green and yellow) comming to the back of the truck. A test light told me that the brown wire was running light, the yellow wire was the left turn signal and the green wire was the right turn signal. The new pigtails came with a black wire and an orange wire. I assumed that the black wire should be hooked to the running lights and the orange wire to the turn signals and hooked them up accordingly. I suspect a ground problem, but I can't find it. Any ideas?