OfficerImpersonator
Seattle-area Rounder
Well,,,,relatively plug and play. I know in the case of my RT it wasn't too difficult. The modulator box has the appropriate terminations on the wires to plug into the headlamp bulb assembly. But, you must find a suitable ground connection and route the daylight photocell sensor wire to a suitable place on the bike. I had to make one hole in the back of my headlamp cover in order to route the daylight sensor. I believe their instructions wanted to mount the box outside of the headlight and route the three wires to the highbeam inside.
I was able to find a ground on one of the metal bulb frames inside the headlight housing, too.
You can see details with photos here:
Your knuckles aren't nearly bloody enough for having been reaching around the back of the headlight area!