Wiring is simple and direct ... I just sent 12 volts through an on/off switch at my dash to the backups ... wired BOTH wires from each bulb to power, make sure your units are grounded well, and you're in business.
I'm going to put a lighted switch on mine so it's obvious when they're on and I don't forget to shut them off. I was forgetting to shut them off the first couple of weeks after I installed them, but now I'm in the habit and I don't forget anymore. They're sure do the job nicely, too!
