Thanks for the info and it is helpful, but my problem is physically getting to the wire coming from the cold side of the brake light switch. The picture and discription is simple enough but the location of that switch is totally unaccessable as near as I can tell. I have the full GM shop manuels for this vehicle and have not been able to find the information I need. I suspect that there is a wire some where that is more accessable that can be tapped for that brake controller. If not I guess I'll have to take the dash apart to get to that wire.
The brake line is actually easy to get at.
The switch actually pulls straight down the pedal shaft.
Crawl into your footwell, and put your hand on the brake pedal shaft. Slide your hand upwards until you find a plastic tab that wraps around the shaft. Grap that plastic piece, and pull straight down. This is the brake switch. It does not look like a normal plunger type switch. This is what throws most people off when they try to find it.
This is what the switch looks like when it's removed.
You can see where I tapped into my wire for my brake controller.
The question is going to probably come up, why did I splice into the white line? I have cruise, and splicing into the red gave undesirable results. For some reason when I would turn on the cruise control the trailer brakes would apply.
Sorry about the fuzzy pics. I guess my lens needs cleaning.