The glass panel is fixed onto the front bezel with fourteen magnets around its perimeter.
Stick two suction cups to opposing corners of the glass panel.
To attach the suction cups we sell, first position the suction cup with the movable handle parallel to the face of the glass panel. While lightly holding the suction cup against the glass, raise the movable handle until it is parallel with the other handle.
If your suction cups refuse to stick, try cleaning both the glass panel and the suction cup with a mild solvent such as Windex.
Gently pull the glass panel straight up off the iMac.
The glass panel has several positioning pins around its perimeter. To avoid shearing these pins off the glass panel, be sure to only pull straight up during removal.
Be meticulous about cleaning the LCD and the inside face of the glass panel before reinstallation, as any fingerprints or dust trapped inside will be annoyingly visible when the display is on.
If necessary, remove the piece of foam tape covering the optical drive thermal sensor.
To remove the optical drive thermal sensor, use the tip of a spudger to lift the center finger of the thermal sensor bracket while applying slight tension to the thermal sensor cable.
If your thermal sensor is stuck to the optical drive, skip to the next step.
Use the flat end of a spudger to pry the optical drive thermal sensor bracket up off the adhesive securing it to the optical drive.
If the adhesive gets dirty or will not stick to your new optical drive, place some double-sided tape under the two semicircular ears of the thermal sensor bracket.