30 Minuten - 2 Stunden
My iPod Classic's battery was shot.
It was cumbersome and not the easiest task to perform, but once I set my mind and determination to it, I completed the job. The case is marred a little, but it was way better than having to buy a whole new iPod or paying $80+ dollars to have an Apple store do it.
Be patient and take your time. The ifixit installation guide was very helpful. The plastic tools that are included in the battery kit are probably only going to be useful for one job. They don't hold up the best, but that's because their tips have to be slim to pry into the iPod case. In the beginning it might not look like they've pried into the case, but they do, enough to get a slim putty knife in between them to open the case further.