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.
Open the rear side door.
Remove the bolts retaining the wedge to the bottom of the door.
Remove the wedge from the door.
Fig 1: Removing Wedge Assembly From Bottom Of Door