Rhino Li-Po Questions

I have a Zippy/Rhino 1750mah 25C 2S Li-Po for my RC18T. They use 12ga wire which is WAY overkill for a 1/18. How hard would it be to disassemble the pack and solder on some thinner wire? Also would I also be able to shorten the balance plug wires? I ordered an extender for my charger so I would be able to use a Li-Po Sack but there is no need to have the balance plug wires be so long with the use of an extender. Oh, and one more thing, what kind of heatshrink should I use when I rebuild the pack?