WARNING: This page is about a different car, the 2003 GMC Sonoma, 2003 GMC Jimmy, 2003 Chevrolet S10 Pickup, and 2003 Chevrolet Blazer. However, it is still accessible from the selected car via links, so may be relevant.
Install the bulb.
Connect the electrical connector.
Fig 1: Connecting Electrical Connector
Courtesy of GENERAL MOTORS CORP.
Install the dome lamp assembly into the headliner.
Snap the lens into place.
Fig 2: Installing Dome Lamp Assembly Into Headliner