Ok, I'm pretty sure I know, but just wanted to run it past our resident rules experts: any factory option that was available for the model/year car listed on the spec line is legal, unless it differs from something listed on the spec line (e.g. trans gear ratios, rotor diameter, etc), right?

For example, the 4th Gen Camaro/Firebird V6 was available with the RS package, which included a factory 'sport appearance package' (still researching, but reportedly includes a ground effects package & different rear spoiler along with badging), and all 4th Gen V6s could be had with the Y87 option, which included dual-outlet exhaust, LSD, and the quicker ratio steering rack (~14:1 v. the std ~16:1), along with rear disc brakes on the '96 - '98 models & shorter gears (3.42 v. 3.08) on the autos.

All of those things would then be legal for IT, right?