An uncoupling tool that a bunch of guys in the modular club I belong to make consists of a piece of 1/2 inch doweling about 4 inches long with a 4 inch pice of thin piano wire glued into a hole drilled in the end. At the end of the wire opposite the dowel handle, you do two 90* bends to make roughly a squared off z shape. To use it, you get slack in your Kadee couplers, and use the wire to "snag" one trip pin and uncouple. It is the best tool I've seen for walk around operations.