To enhance the safety of the ride , and to make sure the guy behind me stops in time I have installed LED lights on the rear of the bike that are on as running lights and flash for 5 seconds when I apply the brakes, you can go to
http://www.hyperlites.com/ to see the different products. Click
here to see a video demonstration.
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As you can see it was installed on a license plate bracket, and does not interfere with the panniers, the wiring was connected to the rear brake and running lights of the bike, and since they are LEDs they don't take much current, and did not effect the GS electrical system.