Removal Procedure

WARNING: This page is about a different car, the 2002 Pontiac Bonneville. However, it is still accessible from the selected car via links, so may be relevant.

Lower the rear of the headliner far enough to access the radio antenna module. Refer to HEADLINER REPLACEMENT (WITHOUT SUNROOF) or HEADLINER REPLACEMENT (WITH SUNROOF) .
Disconnect the electrical connectors from the radio antenna module.
Remove the fastener securing the radio antenna module to the roof beam.
Remove the radio antenna module.

Fig 1: Removing Radio Antenna Module

Courtesy of GENERAL MOTORS CORP.