Oki C 9400 - Manual (Page 313)

6. Unlock the blanking plate by pushing in the direction of the molded-in arrow, then
remove the blanking plate from the drum.
7. Lower the new image drum into the printer, aligning the pins on the ends of the drum
with the slots (indicated by arrows) in the printer.
8. Unpack the new toner cartridge and shake it back and forth to distribute the toner.
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