Panasonic SC-HM910 Service Manual page 23

Step 7 Move the slide plate 1 to forward fully.
Step 8 Install the rear lock. (The claw should be latched.)
Step 9 Install the bottom SW P.C.B. (The claw should be
latched.)
Step 10 Install the tray lock. (The claw should be latched.)
Step 11 Remove the tray lock spring from hook, and then latch
to the tray lock.
Step 12 Install the UP/DOWN gear, change gear, change gear
spring, pulley gear and belt in the order of (1) - (5).
Step 13 Install the gear holder, and then tighten the screw (a).
SC-HM910/SC-HM810
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