What i have is a 66. I bought the universal blinker switch and i have blinkers but no tail or brake lights. the wires are correctly hooked up i did the same on my 63 and worked great. The white wire coming from my headlight switch that goes to the brake switch has no power when i turn the switch on or off. Could this be a bad headlight switch?
ligghts Well i jumped power to the white wire from battery and they come on bright. So im thinking light switch.
Grounding I found out early that most of my electrical problems stemmed from poor grounding. In order to get my rear lights, both taillights and backup light, to work properly I purchased a short battery cable (18") and using self tapping screws I attached one end to the chassis and the other end to the rear bed channel that is located directly underneath the tailgate.(mine is a Fleetside bed) If you have a Stepside bed I'm sure you can find a spot to attach. The main thing you want is make sure the bed is grounded to the chassis.
