Today I measured stall amps in all my locos and determined which, if any, had insulated motors. I noticed that using a continuity meter, if I placed one probe on a motor terminal and the other on any wheel then there would be continuity, so how do you determine which is right side and which is left side rail pick up wire? This is on and older Athearn loco. I am sure someone will inform me of the digitrax decoders specifically for these locos, the problem is that some time ago I removed the tabs and got rid of that massive bulb in the cab, and installed a grain of wheat bulb for the no. boards, I planned on installing a MRC 350 decoder in this Athearn. Should I be checking for continuity between the motor terminals and the wheel or the motor terminals and the metal frame? I have read conflicting info regarding this. Thanks Martin.