I have an'00 Bonneville SSEi and my wife has a '01 Bonneville SE(both of them Dark Maple Red Met,...yes a little bizzare,but true),....I wash and wax both of the cars with the same wax,....but the SSiI Always shines WAY more than the SE,.....it'* a glassy-looking shine[and the car has been through 4 Northern winters(snow,ice,road-salt,etc)],......even when the wax wears off,my car still has a glassy look to the paint.Is there two different kinds/grades of clear-coat that is applied at the factory for Bonnevilles?!?

Not that I've heard of, maybe your car has a dealer applied diamond coat or perma shine?