[coach]

If you have a vice or something to hold the battery still, use it. It will save you time and fussing by getting them oriented correctly before you make your first joint. Same with the wires, if you have a soldering jig with clips to hold then in place, it will free up your hands to hold the iron and solder.

Dry-fit and pre-tin everything. Just remember to let the battery cool down before you proceed to keep temps to a minimum.