Be careful when prying the plastic bezel and back case apart from each other; the parts are connected by both snaps and adhesive. Forcing the back case off could result in it breaking or cracking.

Slide a Plastic Opening Tool in between the front bezel and the back case, slowly working it around the tight edges.

Be patient, it may take several tries to remove the bezel and back case successfully. You may need to slide repeatedly along the edges of the entire phone perimeter to loosen the adhesive between the two pieces.