I have a first generation Macbook. About 2 years ago, the wireless card stopped working, so I purchased an external adapter that I had been using. But then, a few weeks ago, the fan broke, and I decided to try to replace it. Since I was delving into my Macbook anyway, I decided to take the opportunity to also replace the airport card.
The repair took about an hour and went reasonably smoothly. Some of the tape that I was not supposed to rip disintegrated when I touched it, but I have not noticed any repercussions. The new fan and the new Airport card both work.
I don't have too much advice, except that the pictures and the words don't match up for the last few steps of the fan replacement guide. Follow the pictures, not the words.