After reading this thread I too obtained a Navara mirror & fittings (Ebay) and yesterday I fitted it. The only difference is that mine has not got an ON/OFF button. I realised after fitting that the rear of the mirror has its own day/night sensor so although I wired it to the blue & yellow wires any ignition live would have sufficed. But anyway I guess the blue yellow wires are the easiest to tap into.