4way trailer side:

yellow wire left brake/turn
green wire right brake/turn
brown wire tail/tag/marker light
white wire ground

truck side is dependent on the mfr of the converter you bought, so a generic wiring diagram is worthless.

I go to the dside rear light assy and use a test light or multimeter to find the tail, turn, and brake light wires and tap the lside converter wires to those. then I pull the pside and find the r turn wire and tap that. Done. Since the taps are all within the bodywork, corrosion risk is minimum. I leave wire routing in the body as an exercise for the student....

Thanks fastEddy. The gen1 tailight set up uses the same 2 bulbs for running light, brake, and turn. I spliced into the red/green and hoping to get brake and turn lights on the trailer operational. Nothing worked. This has to be easier since there are many gen1 monty's out there trailering stuff. Just looking for specific wire colors on the monty harness that i have to splice my 4 flat into to make things legal.

Thanks to all who input.

Reviving this old post is there a prefered brand of harnesses? Curt, uhaul, reese, etc... I figured I would get this done while waiting for parts for the engine.

I am having some voltmeter issues. Can someone with a trailer harness tell me what color factory wires to tap into. I have ran the right turn signal wire inside tail light assembaly likewise the rest of the wires are ran into the left side assembaly so that all connections will be protected from the elements. I have the Curt harness with the inverter. All I need is to tap into the correct wires. I am going to use one of the tail light mounting screws as a grounding point hopefully. Thanks

You don't need anything fancy, just get the signals from the taillight plugs from the chassis harness. The FSM gives you the wire color codes. No invertor necessary because the stop/signal circuit is the same.

unless I missed it the page is missing 8-194 is the companion to the 8-195 that shows the tail light bulbs, but do not know which is which from what displayed. I figured someone with a wiring harness could tell the colors. if not when I get it figured out I will post up on here to make it easy for the next guy.

it has been a long time and i lost my harness and now finially found it and hooked up. using Curts instructions. i used a test light at the plug and it checks out except for the right turn signal, but when i hook up to the trailer nothing works. i tested the trailer with a lawn mower battery so the trailer is fine. the odd thing is the brake light and turn signal is on the same wire and if i tap it into it nothing works. this has been by far the most confusing wiring project. it should be straight forward but i am getting all kinds of different results. This is very fustrating

Buy a U-Haul or Reese converter and be done with it.

Using your test light, prob the wires on the tail lights to figure what wire is what.

You need a converter, You need a converter, You need a converter in order to light the brake lights.

What about trying a converter...?

I did get one with converter. Curt Manufacturing 56175