HP ZR2040w User Manual page 23

3. Slide the pedestal out of the recess.
4. Remove four screws holding the mounting plate to the head of the pedestal:
Figure 2-15 Removing the Mounting Plate from the Pedestal
5. Remove four screws to separate the mounting plate from its cover:
Figure 2-16 Removing the Cover from the Mounting Plate
Mounting the Monitor to User-Supplied Support Hardware 17