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.
Remove the top and bottom push-pin retainers from the rear side door weatherstrip.
Remove the weatherstrip from the rear door by gently pulling the weatherstrip away from the door.