Trying to get the reverse gear (manual trans) indicator to work on my 70 Chall. Checked switch on trans works fine. Harness from switch goes to bulkhead connection and has a Black/white tracer wire with a female slip connector coming form it on the engine side. Inside I have the light with a single orange wire. I replaced the harness during the resto with a YO for 4 spd. Can anyone tell me how AI can get this to work? (This is a 4 spd conversion)