69 charger.
I just replaced the turn signal mechanism. It fried itself
with the new one the passenger front signal is dim.
brake light were out, but I bypassed them. Also dome light is out.
IT is super frustrating!!!
When I turn the lights on the right turn signal lights up. This is with the key off....Also the right blinker blink both tail lights when the lights are off

 

You're definitely getting a back feed. Many back feeds are caused by a bad ground. Power will search out seeking a ground and often uses a bulb. Check your grounds and bulbs that work off that circuit. The bulbs sometimes get corroded and cause this as well.