I have a '77 F150 4X4 that I have been slowly fixing up and modifying. My current headache is with the lights, turn signals and parking lights to be exact. all lights work except for the front drivers parking lamp and no signals flash. I replaced the flasher relay, and the flashers are working, however the signals still are not. the bulbs are all good. I'm assuming that there is a short somewhere in the line for that bulb. any ideas on how to trace this down.

 

If both the parking lamp and the turn signal do not work on the same bulb holder, I would look at the ground on that side.

Use a meter to check for continuity to ground, and if good, check for power.