There are 2 small wires that follow the steering column down. First you need to check the resistor size that is on your key, and find an in-line resistor at radio shack that is very nearly identical in resistance. Cut the 2 wires on the column and solder in the resistor on the car side of the wires (not to the wires that go up to the key). The computer needs to see this resistance to know that the proper key is in the tumbler.
Go to this site and you will get a very good idea of what to do.
http://newrockies.ca/vatsbypass/