I only ran 2 wires, a 10g hot(connected to both power wires under seat) and 1 ground. Actually, I ran wires to a junction block between the seats, and forked off of that to each seat.
Interior was bare at the time, so running the wires was no problem. The "cooling" part of the seats is simply a fan that circulates air(perforated leather helps), I dont think they are hooked into the AC system at all. Only good for about 15 deg. temp drop, or so I have read.