bluetrevian for his pictures on how to do this.
I noticed immediately that the old lipo was swollen so I was confident that this was indeed the problem. The next concern I had was whether the new lipo would fit. Luckily it did with the help of a Dremel. There is a little tab that secures the old battery. I had to grind it flat, which made the new battery fit PERFECTLY!
I just spliced the existing battery wires, soldering them together and covering the join with heat-shrink.
Hopefully this will help some of you revive your old hardware and prepare you for the next part of my project... more on that next time.