Weird Bulb Behavior

Ok, in an effort to not be that guy who comes here for help, then never updates all the thread contributors...... I had all kinds of weird stuff going on and typically these types of problems are in fact ground issues, but I didn't see anywhere this could be the case.

I installed a new turn signal harness as a craps shot. If that fixed it, then good, if not.... well it should have been replaced anyway. Haha.... But no, it did not fix the problem.

So, I turned my attention to the rear harness. It had been cut into by a previous owner for a third brake light. I removed the third brake light and repaired the wires. This is the only place I could see the harness has been cut in to. At any rate, I just didn't trust the harness. So I bypassed the wires to the tail lights and brake lights with test leads that I made. Everything worked perfectly. So, it's something in the harness. I decided not to spend the money on a reproduction harness, so I ordered the correct color and gauge of primary wire to run new leads.

Thank you all for the input. See ya'll here on the forum.