dp is correct the reverse rev. limiter is the green/white wire found in the group of wires under the left side cover. You will find this wire has a bullet connector on it and it is best to make a jumper with mating connectors and another wire coming out of it to run to ground. This way if you want to take the over ride out all you do is disconnect the over ride and reconnect the original wires together. You could also run a switch in line with the other wire so that it is switchable if you want.
There is a schematic that has been made by a gentleman called Grizzhopper on the High Lifter forum that shows how to over ride both the reverse and diff-lock limiters with one switch. It involves using a relay and switch and is a very clean method to disable the limiters; this is what I have done. I placed the switch just behind the shifter handle on the left side, switch it down and all limiters have been over ridden. I like this method over the permanent method because when it is in the over ride mode the reverse light will blink and not operate properly. And it is only on rare occasion that I really need the over rides.