Apply a suction cup to the bottom edge of the rear glass.

Pull up on the suction cup with firm, constant pressure to create a slight gap between the rear glass and the frame.

If the glass is cracked, the suction cup may not stick. Try lifting it with strong tape, or superglue the suction cup in place and allow it to cure so you can proceed.

This may require a significant amount of force, but you only need to open a very slight gap with the suction cup to insert your tool.

If you have trouble, apply more heat to further soften the adhesive, and try again. The adhesive cools quickly, so you may need to heat it repeatedly.

Insert an opening pick into the gap you created under the rear glass.