Like chris said, they are very sensitive and probably wouldn't take to kindly to being hacked apart. If you decide to give it a go, make sure it is in a peice of pipe of the exact same diameter as the original pipe as well as being mounted in the same position with respect to the pipe.

I don't know exactly how they work but I can imagine that air speed has a fair bit to do with it. If you use a smaller pipe you will get greater air speed and vice versa. The air speed also decreases the closer you get to the pipe walls.

I think it might be possible but you might find that the regular chip used to run a z32 afm may not be right for yours. You would be pioneering!