Bought an extra pair of the blue opening tools ... they both broke trying to open the case. Guess this one was a bit more stubborn. What saved me was the mini-screwdriver on a Leatherman Micro multitool & the iFixIt Metal Spudger.
Insert a plastic opening tool into the seam between the front and back of the iPod.
This is not possible for ipod 6th gen, I think ifitit may did for 5th gen?
It IS possible and it's really REALLY tough. The plastic tool included in this set is enough to keep seams open where they show in steps 2 and 3 just wide enough for you to put something else in there. But to start them, I used an exacto like blade. When I did this job, I had 3 regular spudgers, the 2 tools provided here, 4 different style green spudgers from somewhere else, 5 large 'guitar picks' sold here to cut the glue holding new iMac screens to the case, the metal spudger, and an exacto type blade.
It was still an incredibly laborious job and although the iPod is back together and works perfectly, one of the seams is bent out a little.
Well, *that* was interesting!
Firstly, as a few have mentioned here, the 6th-generation classics are more tightly-sealed than their immediate forebears, so the otherwise-useful plastic tools included in the battery-replacement kit won't cut it all by themselves; artful (and careful!) application of the metal spudger tool was also required. Thankfully, years of freelance IT work on recalcitrant Macs of all stripes helped prepare me for this bit of improvisation, even though this was the first time I've taken a crack at an iPod (my own 120GB classic - thin version). Happily, other than twisting that one metal clip near the headphone jack - apparently impossible to avoid - and some very minor cosmetic damage, the balance of work went without a hitch. I speculate why Apple makes us go though this, but that's for another thread. Thanks for the kit and tools!
LOL! The reason they make it hard to service is that Apple Authorized repair wants $360.00 US to replace the battery!