The Cable Management Tray is designed to accommodate the clamp portion of the monitor arm.
When installing the cable tray with a Jarvis or Pole-Mounted Monitor Arm, the cable tray won’t hang directly under the back of the desktop as shown for the 30" desktops, or slightly forward with the 24" desktops, as shown in the assembly guide.
Instead, we recommend installing the tray in the forward position (just behind the monitor arm clamp), so that the tray itself sticks out slightly from the back of the desk. We also suggest installing the monitor arm first where you would like it located on the desktop, then place the tray over the clamp of the arm and install it as instructed above.