You'll need some battery bars as well to put the individual cells together - get the one's with kinks in.
People use the cell-sized heatshrink to put an extra layer of protection over the individual cells before assembly, and to stop the matchers labels from rubbing off.
The key to assembling a good pack is a good, strong soldering iron (60w+), which means yuou don't have to hold the heat against the cell for too long, avoiding cell damage.
Don't know much about fitting Deans.