SN Electronic Brake controller

[Tucsontoy]

Where does the "red wire" connect? I do not see the old style brake switch on the pedal arm. Is it on the bottom of the master cylinder next to the firewall?

[Tucsontoy]

I never did find a brake switch under the dash on the brake pedal arm. In the engine bay under the brake master there are two gray wires only a couple inches from the fire wall. With the key off, one wire tested hot 12v. The other tested zero volts. With the brake pedal pressed it shows voltage. I could not find any details on this switch so I have to assume it is a pressure switch for the brake lights rather than a button switch like many vehicles. I soldered the red controller wire into this "cold side" wire. Started the rig and it appears to work. Have not hooked up a trailer yet.