Dell E33S001 Owner's Manual page 124

Figure 79. Removing the LED module—four cabled hard drive chassis
1 LED module
3 slot on the chassis
Figure 80. Removing the LED control panel board—four cabled hard drive chassis
1 screw (2)
3 control panel board
5 standoff on the chassis (2)
124 Installing and removing system components
2 screw (2)
2 control panel connector cable
4 USB connector cable