Brother DCP-9055CDN Service Manual page 307

(10) Remove the Develop forced release part from the Forced develop release cam.
(11) Release the two Hooks to remove the Top drive ASSY from the Base frame unit.
Forced develop release cam
Pin
Base frame unit
Hook
Develop forced release part
Hook
Top drive ASSY
<Left side>
Forced develop release cam
Fig. 3-174
Harness routing: Refer to " Top Drive ASSY"
3-126
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