Yes, but the main thing is the revised (read: better) transmission parts. The PCS (pressure control solenoid) was changed, and the 4th gear output shaft is hardened vs 02 down. Those are the two common failure points on the 4T65E (and -HD).
The thing about the HUD and Homelink (Garage Door Opener) is that on 00-02 they were standard, and in 03 they were optional. That'* the only difference. They were only available (AFAIK
) in 00-05 in the SSEi and the GXP, none of the lower models could even special order them.