8.Remove the two screws that attach the USB cover plate to the display head (1) then slide the cover plate off the display head (2). Remove only the cover plate that is in the location where you want to install the USB module.
NOTE: There is a small “fingernail” slot in the center of the interior edge of the USB cover plate that can be used to help slide the cover plate off the unit.
9.Pull the plug that is inserted in the USB port out of the port. 
NOTE: Some models do not have plugs in the USB ports.
Installing Optional Integrated USB Modules 21