Ok. Sorry for the delay. So, if you have an 04, you might have the old style wiring because gm decided to be screwy and only partly change things in 04. Let me know if this is the case. Otherwise, you'll basically only need four wires. You'll connect pin A orange from gp to pin A red/blk g6, pin C orange gp to pin J red/wht g6, It doesn't list the pin for the ground wires, but they're both the only black wires, so connect those (there's a very slight possibility there is no ground wire on the g6 and the ground is through the frame, in which case don't worry about it), the only wire you'll have to run is an accessory wire (so you can't accidentally burn your car down when you leave the heated seat on). Probably easiest place to tap in is the brown wire running down your steering column (make sure you check before using by verifying function with a test light etc).

If you're installing the passenger seat as well, let me know and I'll pull the schematics too!