Andrew, the Stabilitrak option became standard on all models of Devilles in 98, there were quite a few that had it in 97. There are however two types for the Deville, one is for the Deville with CVRSS and one without. The option for brakes would show as ABS/TCS/ICCS2 or ICCS3. The Seville had a different type which was called Stabilitrak 2. If you want to confirm on a 97 if it has it, look between the rear speakers on the parcel shelf, you will find another sensor there, its called a yaw sensor, there is also one on the steering column. There was no way to switch them off as it was so intergrated into the ABS mother system. If you turned off the Traction control you would then have only second gear starts, they did not change this until mid 2000's. I think someone came up with a fix.