Well, I'm happy I didn't hack the plastic and it came out neat. If I had to do it over, I'd put it closer to the blinker because it's obscured by the clutch cable when I'm in riding position and I have to move my head to see it.. The knob is the controller for the CLS heated grips.
I forget where I bought it. Mail order cost was around $40-45. Datel 0-50VDC