I just checked my book. It's not really a code book but it says your car was built in Southgate California and is a super88. The 568C denotes this. The 56 is of course the year. The 8 denotes a super 88. The 88 was a 7 and the 98 was a 9 . The C is what state it was built in. Mine is a 567M. A 88 2drhdtp built in Lansing Michigan. I don't have any other code information handy at the moment. Hope that helps a little. If you buy any cosmetic or sheetmetal parts, the 88 and super 88 are a direct interchange on most parts but there are a lot of differences between them and the 98 so many 98 parts wont fit. It is based on the caddillac platform and the 88 and super88 are based on the buick platform.