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Upgrades 280/280c Upgrade - 29
Upgrading a Duo 250
or 270c
1 Install the original
trackball assembly,
backup battery, and hard
drive on the PowerBook
Duo 280/280c case
bottom/CPU stiffener/
logic board assembly
(see “Trackball
Assembly,” “Backup
Battery,” and “Hard
Drive” in Take Apart).
2 Reassemble the rest of
the unit.