Taking the logic board out is easy. First, look at the back panel, at the top in the middle. If there is a screw there, remove it. Next, lift the tabs on the back and lift the top up. The procedure will be a bit different depending on which model you have here. If you have a regular LC, follow the LC directions. Otherwise, follow the Other directions.
LC: See where the fan and speaker is? Pull the latch at the end of the "assembly" and lift it just a bit. Pull the other latch and remove the whole assembly.
Other: Disconnect the cable going from the fan to the logic board, and remove the fan by releasing the latches.
Disconnect the cables from the logic board and remove the PDS card if one is installed. Pull the latches that hold the logic board into the machine while at the same time sliding the logic board toward the front. Lift the logic board out.
Remove the cover as described in the logic board section. Next disconnect the cables. the power cable has a locking tab. Release the latches holding the hard drive in and lift it up.
Again, there are different procedures for different models.
LC: Disconnect the floppy cable from the logic board, release the latches that hold the floppy drive in, and lift it up.
Other: Disconnect the floppy cable from the logic board, release the two latches, one at each side of the floppy drive and remove the floppy drive.
Information provided by Doug Brown.