Pay careful attention to how the battery holders (the wires at the top) are positioned before removing, especially the springs which are designed to push the battery out when lifted, but if not carefully reinstalled will not allow the battery click into place.

This was a GREAT tutorial.

I did find on step 3 that I could not dislodge the cover with my fingernails. I had to use a jeweler's screwdriver to carefully pry it loose. I also found that it was easier to put the new battery in flat end first and then laying it down and putting the wires into the pocket.

Thanks for sharing.