Replaced my battery just because I was already in there...
30 minuten - 2 uren
I did a compact flash/SDXC replacement for my 120gb iPod Classic 6g's hard drive, and pretty much destroyed the rear outer case in the process. I ordered a new one and figured I might as well change the battery while I was in there, since I have no desire to open that case again.
It went well! The rear case was so messed up that it was not very hard to open the case back up. I removed the old battery, hold button, and headphone jack and installed the new battery and original components in the replacement back cover. It all snapped back together nicely, but I made sure to turn it on and test it before doing so. Other than some slight visible damage on the side of the front cover, my iPod looks great (it stays in a case anyways) and I know I just installed a few more years of solid use.
If you have an iPod Classic 6g I highly suggest just ordering a spare rear cover if you ever need to open your case. The space between the front and rear covers is basically nonexistent making it extremely hard not to bend the back cover in the process.