About a year ago or so I purchase a 2002 STS which had been in an accident and rolled over. Every panel on the car was smashed but interior was perfect. The car had navigation and F55 struts and 17 inch OEM wheels with Michelin tires. I completely stripped both the 2000 and the 2002 Seville and put the 2002 wiring harness, OEM navigation, engine, wheels and interior into the 2000. The 2000 STS was from Georgia so no rust or damage. Everything worked great. About 6 months ago, I purchased a smashed 2003 STS. It also had navigation etc but also had XM radio. I had to change the navigation unit over and add the wiring harness from the xm module to the body harness which was easy to do once I had the manual. Unfortunately the xm radio module can not be interchanged with another vehicle and a new one costs approx $900 Cdn. The solution was to change all modules including the PCM from the 03 Seville. Everything worked as it should so I now have a 2000 Seville with Advanced navigation, tire pressure monitoring, XM radio, back-up sensors, HID headlamps and F55 suspension. What a great car.