I dont want to chase you away from here for good but you want to check into the W body site. Those guys know all there is to know on W's. Body kits have been made for the Supreme, Im unsure of the years and applications but be warned most guys dont like them much due to the odd creases and other extravegent less than necessary body lines most of these aftermarket GFX makers seem unable to resist putting on their kits. Most drivers of American cars like clean body lines.
As I recall Aerofoam made a nice kit for the Supreme but I think they have vanished now. Anyhow if you like your Oldsmobile join the W body forum and remember to come back here and check in.