http://www.moutons.org/sccasolo/This is a little out of date but it should help you figure out your class. From the looks of it you would be in SM. "STREET MOD (SM): All sedans/coupes (models which were originally equipped with a minimum of four seats, four factory seat belts, not sports car based)."
I just started AutoXing this past weekend so I can't help you much more than that.
