97's should still have VATS. Does your key have a little chip in it? If so.. put an ohm meter to each side of the resistor and see what reading it is.
Then do what I did. Solder a resistor of the correct value to the BCM where it needs the signal and unplug the connector to the dash for VATS. Put in alarm system and smile. Cause no one is going to believe you bypassed the theft deterrent when you put in a better theft deterrent.