UPDATE! I have gotten the case open, and unplugged the hard drive. I'm pretty sure its a 4th gen ipod. Its a 20gb model with a blue backlight. Has the regular touch wheel like the new ipods. In 4th gen., there was a 20,40, and 60gb model. Since they were all in the same casing, which means the same size, can i use the 60gb hard drive in the 20gb model?