you wouldn't have to drill through the third brake light. I was thinking of removing a portion of the housing seal and running the wires up through that gap then. upon mounting the third brake then, there may be a slight pinch and some gaps you'd have to fill with rtv. if I ever mount a light bar on the roof for plowing or vol. fire dept response I'll try it.
divi, if you go the cannon plug route, I definitely want to see how you do it. take plenty of pictures