No GCR handy, but I think the rule is:

a. From the factory, it is fine. In other words, if it was bolted on at the factory, you can run it.

b. From the dealer, it is not.

c. The MR2 is the exception, which allows one of the dealer aero kits that ended up on about 90% of these cars.

Guys? I think this is right.