Remove the following ten screws securing the lower case to the upper case:

• Seven 3 mm Phillips screws.
• Three 13.5 mm Phillips screws.

Using both hands, lift the lower case near the vent to pop it off two clips securing it to the upper case.

Remove the lower case and set it aside.

Three special five-point Torx screws secure the battery to the upper case.

Use Apple specialty tool 922-9101 or iFixit's 5-point Torx driver to remove the two exposed five-point Torx security screws along the top edge of the battery.

A common 1.5 mm flathead screwdriver also works well enough to remove the screws.

You do not necessarily have to follow steps 3-6 to remove the battery in order to replace the hard drive. However it is recommended to remove all power sources from electronics before working on them.

Use the tip of a spudger to bend back the finger of the "Warning: Do not remove the battery" sticker while you remove the five-point Torx screw hidden underneath.

Lift the battery by its plastic pull tab and slide it away from the long edge of the upper case.

Do not try to completely remove the battery just yet.

Tilt the battery back enough to access the battery cable connector.

Pull the battery cable connector away from its socket on the logic board and remove the battery from the upper case.

Remove the two Phillips screws securing the hard drive bracket to the upper case.

These screws are captive to the hard drive bracket.

Lift the the retaining bracket out of the upper case.

Lift the hard drive by its pull tab and pull it out of the chassis, minding the cable attaching it to the computer.

Remove the hard drive cable by pulling its connector straight away from the hard drive.