Electric brake controller: Chev S-10 wiring?

[Drinky-Crow]

I'm installing an electric brake controller on my '96 S-10.

I have almost everything done except for tapping into the cold side of the brake light switch. The instruction sheet that came with the controller does not have any info for the S-10.

I can see the brake light switch attached to a bracket above the brake pedal, but the wires exit the top of the switch, and go up in behind the gauge cluster (as seen from the bottom). I can't see or reach any of the wires.

There's a large connector below and in front of the brake light switch, with 20 or 25 wires of different sizes; is one of these from the brake light switch?