Instrument Dimming

I have a 2003 Chevy Silverado C3500 Ext Cab Dually DURAMAX 2 wheel drive. I am adding some gages to it. I know that the dimming power for the lights in the switches on the door panel (power mirror control and power window control) comes through a connector that plugs in to the front of the fuse panel that is on the left instrument panel.

Does anyone know what pins this power is on or what the wire colors are on the harness that goes out to the door?