H2.0 hex key
Disconnect the power cord cable.
Remove 4 coarse thread screws with an H2.0 hex key.
Remove 7 fine thread screws with an H2.0 hex key.
Remove the rear panel from the printer.
Install the rear panel to the back of the printer.
Lock in the 7 fine thread screws that fix the rear panel.
Lock into 4 coarse threaded screws that fix parts.
Check the appearance and confirm that there is no abnormality.