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 door opening weatherstrip from the door opening.
Gently pull the weatherstrip from the pinch weld flange.
Fig 1: Removing Door Opening Weatherstrip From Door Opening