JD,

Typically, the batteries in a pack are glued together, and then the way the tabs are welded together, would make it a bit difficult to make the switch. it can be done, but you would have to cut a tab between the center two cells, then take the two packs of two cells, glue them side by side to make the square shape, then you would have to solder a jumper where you cut the tab.

Can it be done? Yes..
is it safe? If =done correctly, yes.
is it worth it??  IMHO Nope!!

Craig.
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