The spring screws here are very hard to remove.. the posts holding them down to the logic board popped off for me, and I wasn't about to remove the logic board to re-solder them. I couldn't even get them apart after they were out though! All I did was re-apply thermal paste to the CPU and thermal pads to the GPU and Northbridge chip, and them put on the heatsink without the two spring screws. It keeps cool temperatures, (118* F after normal web browsing for about an hour), which is pretty good still. Just some reassurement for anyone with the same issue. :)
Man, this step is really hard. The hardest step of the iBook guide. It is possible to carefully wiggle it out. Bit by bit, wiggle the plug gently back and forth ever so slightly, so that it comes out. It is SO easy to break it. I've done it before. With patience, it can be done. Just take your time.
On the 1.33 Ghz and 1.42 Ghz, there is a different hard drive connector, and is easier to remove. Also on these two specific models the airport card is not above the RAM, it is to the left of the heatsink, on the logic board. Pretty great guide! I always love ifixit's guides.