I need help. I have 67 and the left turn signal indicator was not working. I figured it would be easier to just pull the bezel out and change all of the bulbs. I discovered that the generator plug was in the right turn signal, not the 194 bulb as required. So I switched all the bulbs out for new, along with the external tail light bulbs. Put back together and issue: Activating the turn signal in either direction makes all four flash, turning on the headlights stops the flashing and with the headlights off, if I depress the brake pedal the right side, fuel gauge pod turns on the back lighting.

Sorry for the first post being a problem, but hopefully someone can help.

 

Sounds like you may have a poor ground attachment under the dash, causing electrical feedback gremlins.

 

Sounds about right. I've got turn signals now on both sides, however with the right turn signal flashing, my right fuel gauge back lighting and the back lighting to the heater control flashes.