yes, it has been done...many times
you should probably try the search feature...i know i have seen 2 or 3 threards on this same topic in the last month alone.
you dont NEED a relay but if you dont use one you could mess something up. there are a few ways to do it:
1) indepentant wiring and switch, no relay
2) #1 with relay
3) tap into paking lights or headlights, no relay (bad idea)
4) #3 with independant power lines, but a relay that is switched from parking lights (like mine) or headlights
i am sure there are others but i recommend going to autozone and getting the $5 wiring kit plus the non-piaa or pilot $4 relay.
they both have instructions the only thing that it doesnt explain is hooking into the parking lights for a switch, which you fing the bulb for the parkin lights that stays solid (usually in the corner) turn them on and use a tester to determine which is ground and which is controled 12v,
then splice in for the switch part of the relay. ground the realy to the hoodlatch, run the power line to the battery (make sure you will have access to the inline fuse in case it blows) and run your power to the lights. dont foget to ground the lights too, but i just tapped them into the ground for the relay.
