Post #7 refers to the factory GPS plug as mentioned, it is part of the DIN socket circuit you asked about. It is three pin. You can buy a matching connector with three wires loose for your connection OEM PN 8 33 004 13 585. It is labled, pin #1 is ground, #2 is a pulse from bike computer for the GPS, Pin #3 is 12 VDC. So you will need to hook up to a dc to dc converter for 5 vdc used by your GPS. It stays hot for 60 seconds after you turn off the key.
It will be cloth tape wrapped to a support just in front on the right side and have a plastic cap inserted to seal it. I suppose you could just cut the bike side connector off and work from there but personally I can't.
Mount Vernon, WA.
tire guy, I'll mount your tires.