Sony PCV-RX551 System Reference Manual page 53

Removing, Installing, and Replacing Components
6
Slide the drive holder up and out.
7
Slide the new drive into the bottom part of the drive holder and align
the holes on each side of the drive holder.
8
Secure the drive to the drive holder using screws in each of the two
holes on each side of the drive holder (screws are provided with the
new drive). Do not overtighten the screws.
9
Slide the drive holder back into the chassis so that the edge of the
holder is flush with the chassis.
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