modifying your harness is not nesessary. if you don't allready know, the lights just unplug and nothing else is affected. if your going to remove all of the lighting related wires from your harness(es), that sounds like quite the project. :wacko:
the service manual has a wiring diagram in the back that can help you follow the wires, but they are all wrapped together with tape from what i've seen. i suppose it can be done though.
if your going to remove your light switch, that unplugs too. if you want to add a tether kill switch, use the green & blk/whi wires. if i have caused you to have more questions, ask away!