WARNING: This page is about a different car, the 2003 Oldsmobile Bravada, 2003 GMC Envoy XL, 2003 GMC Envoy, and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
Open the lift gate window.
Remove the nuts retaining the striker assembly to the lift gate window.
Remove the handle and striker assembly from the lift gate window.
Fig 1: Handle And Striker Assembly From Lift Gate Window