I have just installed one of these:

http://www.dealextreme.com/p/gps-dualband-...cker-22968

For a cheap unit it works surprisingly well. It responds with the location on an SMS after receiving an SMS with the command and password.

I am about to complete the final part of the installation by attaching the output that allows the vehicle to be shut down. The manual suggests that it is attached to the fuel pump relay, but I am a little worried about messing with this area. One idea I had was to put the output to the fuse that puts the transfer box in neutral, but this is probably not good to do if the car is in motion.

Has anyone else installed a tracker before with the ability to disable a vehicle?

Mine is an 03 TD6.

Thanks

Jack