WARNING: This page is about a different car, the 2003 GMC Safari and 2003 Chevrolet Astro. However, it is still accessible from the selected car via links, so may be relevant.
Align the grill retaining clips with the slots in the door trim panel.
Seat the grille into place.
Close the door(s).
Fig 1: Installing Rear Speaker Grille To The Door Trim Panel