Hello Folks, Have a problem. I have installed a simple sound unit in this car, using Mantua tender trucks. The screw running up through the bolster provides a connection point for the needed track power. These are the simple connections: a wire to each truck; two wires to speaker; 9 volt battery plug. As you know, Mantua's trucks have two brass wheels on one side; two plastic on other. These wheels of course, are on opposite sides of the car when mounted. When I placed the car on the track and applied power, nothing. Then I accidentally derailed the trucks, so that only one brass wheel on each truck was touching their respective track. Got sound! My question is, now what orientation of the wheels is the correct one. Obviously, the standard Mantua arrangement does not work. Do I rotate an axle on each truck, so that each truck has a brass wheel on each rail? If so, is there a particluar orientation for the 'opposite' brass wheels, i.e. should the two end axles have brass on the 'inner' track (track farthest from viewer). It seems to me that orientation shouldn't matter....so what's going on?