I’ve replaced a few dozen iPod batteries, and only scratched 2 of them doing it… Fortunately, they were both mine. ;-)

There are 2 tricks-

1) Throw away whatever you’re using to pry the side of it open, unless its a tempered stainless steel knife. Screwdrivers are crap- they’re too big to get between the two halves properly, without marring the finish. I use the blade on a Leatherman Wave multi-tool.

2) Take your time. Rushing it doesn’t help. I’m an ace at it, and it still takes me 20 minutes or so to crack ‘em open.

Once its open, its a breeze.

I can give more interactive help, if needed.