Dell 2130cn Service Manual page 694

Chapter 3 Removal and Replacement Procedures (RRPs)
Replacement 47 TRAY EXT (PL1.1.2)
1) Mate the boss of the TRAY EXT with the
hole of the COVER ASSY TOP.
2) Mate the other boss of the TRAY EXT
with the hole of the COVER ASSY TOP.
3) Close the TRAY EXT.
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