Breathe deeply. Trying times are ahead, but we promise the lower case does come off.
Push the thin rims of the lower case surrounding the battery compartment in, bending them past the tabs, and then lift up to free that corner of the lower case.
There is a slot on the wall of the battery compartment that locks the lower case in place. Use a small flathead screwdriver to pry out the slot's lower rim and pull up on the lower case to free the slot from the tabs holding it.
Run a spudger along the seam between the lower case and upper case on the front of the computer to free the tabs locking the lower case. Pull up on the lower case and continue to use the spudger as necessary until you hear three distinct clicks.
Continue to run the spudger around the front right corner. There are two tabs on the port side of the computer, one near the front corner and one near the sound-out port.
There are three tabs over the optical drive that must be released before the lower case can come off. Slide the spudger into the lower case above the optical drive and run it toward the back of the computer until you hear three distinct clicks.
Before you can yank the upper case off, you must disconnect the trackpad connector, the blue and white power cable, and speaker cable as described in the next steps. Be especially careful with these cables; never pull directly on the cables, but use a spudger to pry up the connector directly.
Carefully lift the upper case slightly and move it toward the front of the computer to reveal the trackpad connector. Use a spudger or your finger to disconnect the trackpad connector hidden beneath the white plastic tab.
After disconnecting the track pad connector, carefully rotate the upper case away from you and rest it against the display.
The connectors at the ends of the following cables are attached very firmly to the sockets on the logic board. Pulling directly on the cable will either separate the cable from its connector or the socket from the logic board.
Use the sharp end of a spudger to disconnect the speaker cable connector.
Lift the top shield up from the right side, minding the upper left corner, which may catch on the metal framework.
When reassembling, make sure you pull the antenna cable all the way through the slot in the middle. It is extremely hard to pull it back through after the top shield is screwed back in.
When replacing the modem, seat the shield first, and then connect the modem and press it firmly into the shield, making sure that it is connected to the logic board.
Using a spudger, pry up the AirPort/Bluetooth board from the end closest to the hard drive. Be sure to pry against the metal framework, as shown in the picture.
The cable you're about to remove is very fragile - do not pull directly on the wires. Instead, try to pry up the connector directly, using a spudger or a small flathead screwdriver if necessary.
Disconnect the microphone cable at the front of the computer, between the left side of the hard drive and the metal framework, removing tape as necessary.
Although not absolutely essential, removal of the hard drive will give enough space to remove the connector with your fingers.
Use a 1.5mm hex screwdriver to remove the two hex screws on either side of the display (four screws total).
If you don't have a 1.5mm hex driver, you can probably get these screws out with a T6 Torx screwdriver. However, if you use a T6 Torx driver you'll be more likely to strip the screws.
Insert the flat end of a spudger perpendicular to the face of the display into the gap between the front and rear bezels near the upper left corner of the display.
Rotate the spudger away from the display to pry the rear bezel off the front bezel.
Gently peel the inverter cable ground strap off the cast aluminum frame of the clutch hinges.
While pulling the inverter cable away from its socket on the inverter board, use the tip of a spudger to push the connector out of its socket.
If the connector won't budge from its socket, insert a metal spudger or similar tool into the gap between the connector and its socket and twist to separate the two pieces.