Get a resistance meter out and measure the resistance across the rotor arm, if its not almost exactly zero, then its probably got the resistor in it.
Get a dremel out and remove it all, then solder in a flat bit of copper or something similar that conducts much better, then epoxy resin over it to make sure it stays in one piece.

Ill try and dig out an article with pictures on it, as my mate took pictures when he did i think.

Back in a few mins mate.