You're pulling too many amps through the switch. Consider strongly a headlight relay under the hood and running heavier gauge wire for both 12V feed through the relay AND ground back to the battery or at least a ground buss. I DON'T KNOW THE FORMULA, but I'd run 10 gauge wire considering you're pulling about 700 watts.
I dream of living in a world where chickens can cross the road and not have their motives questioned.
Be kind. If for no other reason, it will confuse the daylights out of people and make them wonder what you're up to.