WARNING: This page is about a different car, the 2003 Buick Regal and 2003 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
Remove the right and left side air baffle push-in retainers.
Remove the right and left side air baffles.
Fig 1: Removing Right And Left Side Air Baffles & Push-In Retainers