Mine were screwed in and urethaned. I believe the factory switched from silicone to urethane a few years ago. Use the edge of a putty knife to gently and gradually break the adhesive bond, and pry the tray off. Mine had four gobs of urethane under each tray where the four screws were placed. It is pretty easy, and just take your time knifing through the adhesive. Some will heat the edge of the knife, but I did not find it necessary. Fill the old screw holes with silicone, 3M 4200, or fibreglass resin. I used stainless screws and urethane adhesive to install the new one.
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