I'll append the information already available, and explain in more detail what I did to my gps antenna. This mini-coax is NOT standard size. I was using extron BNC's for mini-coax and had to hammer the sleeve out with a tweeker to make it just a little (little) bit bigger. I put a male BNC on both ends of the GPS antenna I cut. I then used 2 female bnc ends (premades that were chopped) to extend to the blank switched next to the steering wheel (also where the VCC wire is on a toggle) and used this switch (http://www.philmore-datak.com/mc/Page%20187.pdf). it shoulc be available at any local electronics store. Here in Calgary I got it at B&E Electronics.

From there I cut back the sleeve on the mini coax. groupped the ground wires together and crimped them with a butt connecter. then I soldered the center conducter to the 2 pins on the toggle and used lots of heat shrink to make it look good.

This does totally screw up your location but it bounces back after roughly 30-45 seconds. I didn't notice adverse effect on milage and speed. but the calculations in the center dial (instant milage, average trip milage and average speed) remained acurate. I assume this is because those calculations are not handled by the gps.

Anyways, I'm more than willing to help anyone get it right if I can. but I really do have to stress. If your not comfortable with this...PLEASE don't do it.

 

it is not as easy as grounding the parking brake wire, The thing on ebay does technically disbale it but in a weird way, the only way to do this is it disable to the gps, cause theres a sensor on it that can tell when your moving.