Over December, my 2009 Macbook had a little water spillage. Now, the tab and tilde key do not work, and it's a pain to use whenever I need to write a paper (I'm in college). I saw on ifixit that they have a replacement keyboard and a guide on how to: Has anyone done this? Is it easy enough to do by yourself? Or is it worth dishing out an extra 150 to get it replaced by a professional?