Dell OptiPlex 9020 (Mid 2013) - Manual (Page 9)

Installing the Cover
1. Place the cover on the chassis.
2. Press down on the cover till it clicks into place.
3. Follow the procedures in After Working Inside Your Computer .
Removing the Front Bezel
1. Follow the procedures in Before Working Inside Your Computer .
2. Remove the cover.
3. Pry the front bezel retention clips away from the chassis.
4. Rotate the bezel away from the computer to release the hooks on the opposite edge of the bezel from the chassis.
Then, lift the chassis and remove the front bezel from the computer.
9