These cars were modified after assembly by , I believe a company called CARS AND CONCEPTS. During the production run part numbers for air dams, sway bars and aux lights were in a supplemental parts book for Cad. dealers. I believe the front sway bar was the same except for stiffness of the bushings, the rear bar was in fact fatter. If you are a new owner of this era of Cadillac, please follow the cooling instructions on the panel in front of the radiator! It says to replace coolant every 24 months and install cooling system sealer at that time. Please do this as soon as possible, no way to know when was done last. This is critical to life of engine! Also I recc. using DELO brand 15/40 wt oil. The sealer or "pellets" can be gotten at any GM parts dept or BARSLEAK GOLD is the same thru parts retailer. Good luck, you have a low production car! If the sunroof is not factory, there should be a decal on the driver door jamb telling who did it. Also aftermarket sun roofs had a chrome handle to shut the sun shade, factory did not if I remember correctly.