turn on lights through auxillary relay

I am an installer over at circuit city and I havce a customer who purchased two 12volt spot lights that he wants wired into his alarm system as the auxillary function on the remote.  So when he hits aux, his lights on the outside will turn on..  How would I wire the relay to do that, im not so good with relays.

85 aux channel 86 & 87 really really good 12v source where you wont blow the car fuse (Put a 30A fuse on this wire!!!!) 30 output to the spotlight change aux channel to latched or timed for the customer and do it for free too, cuz you got this info free of charge I dont know how much current the spotlight draw, you might have to adjust fuse accordingly BTW, how long you be certified installer? and working at CC?