HP Compaq nc6220 - Notebook PC Maintenance And Service Manual page 143

7. Lift the rear edge of the top cover 1 until it disengages from
the left and right sides of the base enclosure.
8. Lift the top cover 2 straight up and remove it.
Releasing the Top Cover
Reverse the above procedure to install the top cover.
Maintenance and Service Guide
Removal and Replacement Procedures
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