headlights and foglights

Does anybody know where I could get a wire harness to keep my low beams and fog lights on when I turn my high beams on? Or does anybody know to do it yourself. I read on another forum to take a relay out, not sure which one. But to take it out and break off a tab and put it back in. And it would keep the high beams from cutting off the power to the fog lights. But I don't wanna be guessing and breaking relays on a brand new truck if I don't have to. And I'm sure somebody makes a harness. I just can't find one thanks.