I did the same thing to my 1988 M998.
I bought the same switch as the above but for whatever reason I already had one in my shifter ?
So I wired that to similar lights and bam we have backup lights.
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I also added a small (but super bright) light bar under the back bumper angled towards the street that comes on along with the two backup lights
when the truck is put into reverse (as well as the backup camera too). I did this on a old lifted Jeep Grand Wagoneer I had and I cant tell you how
easier it makes parking these trucks at night when you can actually see.
Should of been a AM General factory option !
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