File:Mainboard235.jpg

Picture of the mainboard of the Thinkpad 235 with screws relevant to dismantling circled.

Since there does not seem to be any manual in latin characters for the 235, you may find this useful.

As often the main problem is NOT to remove all screws blindly but only the ones needed, among other to avoid removing bolts and losing nuts inside the case. So read on for details. Also be extremely careful when removing cables, since the plugs on the mainboard are very fragile and easy to break (happened to me).

Remove the keyboard: 2 screws, one on each side of the case.

Remove the plastic part hiding the screen hinge: 2 screws on the back, then unfold the screen at most.

Now see picture (with Cardbus slot covered for a better contrast). First remove the processor heatsink in the upper right corner: 3 screws circled in blue. Finally remove the mainboard itself: 6 screws circled in red. 2 screws underneath the case (they go through the right end of the double CardBus slot), 2 in the right corners of the case (one in each), 1 in the center of the white plastic piece in the middle, and last 1 in the bottom left just below the same CardBus slot. Now don't forget to remove the power switch.

Once the mainboard is detached, removing further (sub-)parts becomes very easy since nothing is hidden anymore.

External Sources

More detailed/better instructions