Hi! I recently bought an eMac off of craigslist. The original specs were 1GHz/128 mb ram/CD Drive. I upgraded the rab to 768 mb, soon to be 1 GB. Now, how hard is it to replace the disc drive? I tried to install via target disc from my old TiBook (it started running again, yay!) but the disc drive crapped out during install I think. How hard is it to replace the disc drive? Also, the error I got during the install was something along the lines of "could not validate essentials" or something like that. What does that mean? I hope I don't have to get a new disc, I don't have the money. Thanks!!!