Lenovo ThinkStation P7 Manual page 22

15. On the back of the system chassis there are two locations for storage of
key carriers for both the side door keys and the FLEX bay keys, as needed.
If there is no lock for the side door, both of these locations will be available.
Both locations are identical and either can be used.
16. On the bottom of the key carrier, locate the two mounting tabs. Note the
open end with the center guide on each tab.
17. Position the carrier to insert the open end of the tabs into the notches on
one of the key carrier mount locations. Line up the center guides on the
carrier with the openings in the center of the notches
18. Slide the carrier into the notches until the catch on the end of the carrier,
seen below, locks into place. If it does not slide into place easily, it may be
necessary to put pressure on the carrier, directly over each tab.
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