Marty from Sunny Florida wrote:

A power port (cigarette lighter 12v) adapter.

I wired a DC/DC voltage converter to ours. Take the supply from the
breaker to the power port and hook that to the input of the converter.
Hook the 13v output to the power port. The shelf on top of the glove box
makes a good mounting place...

The flying lead version found here is portable:
http://www.powerstream.com/dc1.htm

I used the 15 amp model... $51