If both wires are red, you'll have to experiment to find out which one is positive or negative. If they're like all of the LEDs I've seen, you won't damage anything by hooking them up backwards.
If they are a single function LED (all of the lights come on at once, and there's only the two wires coming out the back), grab a set of TAC units from us- they connect to your running, brake, and turn signal lights, and give you a single output to the LED. Good luck!
-Phil at FBI
also your local auto parts store sells trailer hook up converter youll need to make the 2 wire convert to a 3 wire set up. leds are diodes, diodes only allow current to flow one direction, so hook your lights up to your battery, and find out which one is positive and which is negative