Old battery in my original iPod 3G finally would no longer retain its charge.
Considering the trepidation with which I have always approached electronics and my total lack of experience in their repair, I would say it went very well. Originally I thought the black covering of the battery was for shipping but I was able to replace it before its installation.
The only (surmountable) difficulty occurred when it was time to route the 3 small wires to attach their plug to the logic board. The wires on the replacement battery were of somewhat larger calibre than those on the original harness.