Difficulty: For advanced users. (You assume all risk in doing this; if something gets damaged in the process, the Apple warranty won't cover it.)

Tools needed:

• Phillips driver (very small)
• small screwdriver
• small hex-wrench (6mm)
• tweezers

(Note: You should use a 2.5in hard drive with a max height of 9.5mm. Although one reader in the past put a 12.5mm hard drive in a PB G4 12in model, the taller drive blocks airflow inside the case. 9.5mm high hard drives are currently available in sizes up to 80GB. Hitachi 80GB 9.5mm notebook drive reviewed here recently.)

Remove battery, then remove memory access plate (4 screws).

Remove black screw (marked yellow), then remove memory module.

Remove 3 screws in battery bay (marked yellow).

Clip out the keys F1, F2, F11, F12 with a small, flat screwdriver.

Two small screws are hidden under two small covers; remove them with the tweezers.

Remove the two hex-screws with the hex-wrench (6).

Remove the 4 screws on the rear side, the 2 on the left, and the 2 on the right side of the case.

Now you can remove the keyboard by flipping the keyboard towards you. Be careful with the flat ribbon cable that is fixed with a silver foil. Remove that too.

Here you can see the silver foil (I put it on the right side...)
Pull out the flat ribbon cable... but don't break it!!! Very gently please!!!

There are 3 more cables hidden under 2 more silver foils. Pull them out very carefully, as there are very thin cables on the connectors. Next remove all screws you see on the aluminum plate (approx. 10 or 11), note which screw goes where because they differ in size.

After all screws are removed you can take off the upper piece of the case. To do so you have to raise the piece while you are clipping out the clips holding the case in place. Use your fingernails for that, they won't harm the surface of the Powerbook. But be careful, these clips tend to break very easily.
Now the powerbook is lying with open guts in front of you

• Unplug the hard disk cable (marked yellow, be careful!!!)
• Remove 2 screws (marked yellow)
• The harddisk can be removed now.

Plug the cable onto your new harddrive and exchange the rubber shock protection and the metal mounting plate from your old drive to your new hard disk.
Assemble your powerbook the reverse way you disassembled it.
-Stefan