well if you run 1/2 the power through a resister, so you can run it on 4 batteries in seires, then you would be better off tossing out 2 of the batteries instead (i think).
the closer you can get to direct drive, the less waste you will have at any rate. dont they have 2xD holders now? its not to late to take it back /ubbthreads/images/graemlins/smile.gif
you can rewire that thing, with a wire cutter, some wire and a soldering gun. and they need to be totally rebuilt anyways to keep the rivets held still anyways , junk that they are /ubbthreads/images/graemlins/smile.gif