Jack it up, Spin the wheel by hand, If they other spins the same way you have an LSD therefore a Cup equipped car. It should be quite clear just by driving it anyway if it is a Cup or Sport.
Yes red calipers, and have diff, but could that not be fitted to sports chassis, notice nothing in vin to ident chassis type, was hoping for something official
Not the door pillar Dinn, the sticker inside the door frame fitted at the factory will state if the car is cup spec.
If you have an LSD along with red callipers/Grooved discs then you have a Cup chassis, Simple. Regardless if its a Sport with the "Cup pack" it is still a Cup chassis...