Be very careful not to touch the capacitor leads or any exposed solder joints on the back of the power supply (boxed in red).

Grasp the small tab at the end of one of the bottom edge display adhesive strips and pull the adhesive toward the top of the iMac to remove it.

Repeat this step with the other adhesive strip and remove it.

If either adhesive strip breaks before it's removed, use a plastic card to slice through the remaining adhesive.