Reverse Light

1994 Kenworth W900L has no reverse light installed. I'd like to install one even though I'm not sure if it's even required since the fog lights on my headache rack can suffice. Anyway, there are three wires hanging near the hole but none have power after checking with a test light. Maybe I'm testing the wires wrong? One is white and has a clasp on the end as if to attach to a ground so I've been assuming that's the ground wire. The other two have paint on them and cannot tell exactly what color they are but both have the male prong type terminals in them.

My light only has two wires so I have no idea which wires to connect. Input?

Also, is there a fuse for the reverse light? I don't see one specifically labelled for the reverse light but i've heard they can sometimes been tied into other circuits.

How about the reverse light switch that usually on the transmission? It's an Eaton 13 speed and I've read here that on 379s their under the panel where the boot is at the bottom of the shifter. Are they located in the same place on a W9?

 

Thanks for the input. I removed the shifter boot and was able to locate the back up switch. After using my test light to confirm it was working properly I scoured the harness traveling the frame. I was unable to determine the break in continuity so I opted to run a new wire from the switch to the light. Problem solved!