Why not just parallell them for a while? Voltage should be equal on all cells then. Notice that you MUST disconnect the series connection first!
Ok, that is true (but still for free).Well for one its a PITA since he's already installed the pack.....
its much easier to put a single cell charger on each one for a little while and do it that way.
As far as isolated chargers, you really only need one if you're using multiple chargers at the same time.