WARNING: This page is about a different car, the 2002 Oldsmobile Bravada, 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
Remove the bolt that retains the seat belt upper anchor to the body.
Remove the garnish molding from the vehicle.
Fig 1: Identifying Garnish Molding - Body Side Window - Front (TrailBlazer EXT, Envoy XL)