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.
The connectors at the ends of the 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.
Lift the upper case enough to disconnect the blue and white power cable from the logic board.
Using your fingernails or a dental pick, carefully pry the connector from its socket.
Make sure you are pulling only on the connector and not on the socket.
If you have already removed the yellow tape, skip this step.
Peel back three strips of yellow tape in the bottom, left corner.
Peel back one strip of foil tape near the audio-out port, one near where the trackpad connects to the logic board, and one near where the screen latch used to be.
Use a 1.5 mm hex screwdriver to remove the two hex screws on either side of the display (four screws total).
If you don't have a 1.5 mm 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.
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.