You really have to dig for the accessory plug under the seat. In fact, I had to take the battery out and that plug and the B+ plug were just in front of the battery, at the very bottom, zip tied to the cross piece.
The accessory plug has 4 contacts. One is switched by the switch in the dash (ignition must be on), one on by the ignition, one triggered by the running/brake lights and a ground.
The adjacent B+ connector is always hot and runs straight from the battery through the main, 40A, fuse.

 

Has anyone actually installed an accessory switch? I have A switch that matches the oem style, the previous owner knocked out one of the knock outs and installed a gawdy chrome round toggle switch for the running lights. I want to use the switch I have instead, but found no ''diy'' on the subject.
Any Help would be appreciated.