I don't reccomend takign apart a powerbook. I had some idiot who claimed he was a tech open my powerbook (he lied and wasn't a tech), broke something on the inside and the applecare was voided....the outcome = me selling everything I own to buy another Powerbook for $2000.00 only to have my little cousin spill a slushie drink on it, voiding the apple care again resulting in me going bankrupt and buying another powerbook :S. Is your machine under applecare still?
To take the keyboard out, remove the RAM slot cover at the bottom-end of the PowerBook G4. (4 screws.) In there, a little hidden, there should be a longer black screw that has to come out. (1 screw total.)
Flip the PowerBook G4 back around and open the display. Rip off the F1/F2 & F11/F12 keys. In between each of the F-keys, there will be a gray round sticker covering a hidden screw. Remove each screw from each end. (2 screws total.)
Once that's done, pull the keyboard upwards towards you to lift it out of place. Disconnect it from the logic board to properly clean it.
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