Did you find any answers or try it yourself? I am going to be trying this in the very near future, will let you know if I have any luck.
Dont have the heaters yet, I think I might be able to tap into the lifter on the drivers seat, as I have the base model G6, that might save me from having to go deeper into the car.what wires do you have to the heater harness? you should just be able to tap into one of the fuses in the fuse box that are ignitioned fuses and just ground to the ground points. but without knowing th other wires i dont know what else you would need to do. mine has aftermarket seat heaters but i had them professionally installed