Not for the faint-harted.
I would only do this if you are seriously experienced pulling these things apart. It's a bitch to do, and it's very easy to rip ribbon cables along the way (like I did!
If you REALLY want to try, there was a post a long while back (unfortunately in German) so you can at least see what has to be done.http://www.user2user.info/forum/note...pic.php?t=2259
But as I said, even if you understand German, he doesn't make clear one or two crucial places where there is an extra screw to undo, or cable to be careful of, so watch out.
Once you get the keyboard lifted up, there is another screw underneath before the top will come off. And CAREFULLY remove the ribbon cables before doing so.
Basically, I would just send it in. I lot less of a headache!
And even after I managed to replace the drive with a 7200RPM, I had to undo it all, because the 7200 drive was too noisy and vibrated. There was so little dampening in the unit that it couldn't really take a 7200 drive without vibrating. So it was all for nothing anyway!