There is a better way to go. There is a guy on another forum that is making a kit that plugs into the stock harness and works awesome. I can assure you that it works and is plug and play.
Pm me or email me and I will send back the link. I don't know how the admins would feel about posting from a different forum here. Since I am new to this one, I do not want to make any waves.
But the short of it is, this kit works, simple to install. Uses less than 1 watt of power and you have hot grips at idle. I am speaking from experience. It took me about 45 minutes to hook up and put the hood back on. I have used them at -20F and had warm hands. We were running a long trip so I used gauntlets just to keep the wind off, but my hands were comfy warm.