Dell Precision 330 Service Manual page 21

Hold the cover at a slight angle as shown in the following figure.
a
While aligning the top of the cover with the top of the chassis,
insert the three hooks on the cover into the three recessed slots on
the computer chassis.
Rotate the cover downward toward the bottom of the chassis.
b
With both hands, press against the bottom edge of the cover to
ensure that the securing hooks at the bottom of the cover click
into place.
R e p l a c i n g t h e C o v e r ( M i n i To w e r C h a s s i s )
Slide the two parts of the padlock ring together to lock the cover
c
release mechanism.
hook
recessed slot
Co m p ut e r Co v e r
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