Loosen the nut in the upper right and rotate the pie piece until the reverse lights are working. It's easier if you turn the ignition to on, put it in reverse, and have a second person tell you when the lights come on.
I use a slightly different approach to the adjustment.
I rotate the switch until the back up lights are off, then go the opposite direction (moving very slowly) until they come on.
I note that position.
I continue to rotate the switch until the lights just go out again.
I note
that position.
Rotate the switch until the lights come back on.
Then, I center the switch between the two "ON" locations. I have found this to get the most reliable results.
When you "rebuild" the NSS, be sure to replace the dielectric grease that you will be cleaning out. What you are going to find will, most likely, be a rather nasty brown, thick (almost solid) mass of yuck. I also like to lightly burnish the contacts with a pencil eraser just to make sure the contacts are clean.
If you like, you can use an OHM Meter to monitor the switch position instead of using a second person watching the lights. In this manner, the adjustment can be made with the wiring disconnected from the Jeep. Personally, I use a meter.
This is one of the easiest projects to do and it is by far, the most cost effective project as the switch does not get replaced.
BTW, watch out for the little spring that holds the moving contact against the fixed contacts. It has a tendency to jump out...