No thats not the parking brake light on the dash, thats the DRL indicator. The parking brake is in no way hooked up in my mod. All you are doing is giving a GROUND signal to the navigation unit. Thats basically what your parking brake does when you have it up, it sends a GROUND signal to anything that's hooked up to it.
I drove to work today with my hack and it kept me busy during traffic. Probably was a little dangerous playing with it in stop/go - low speed traffic. Oh well, at least I know it works. No more having to pull over to side of road.