Here ya go Larry a concrete example. I converted a K-Line Berkshire, with the same forward facing RS385 motor, to PS3 for a friend. With the K-Line chassis and motor the locomotive just doesn't have the low speed torque/smoothness to run cleanly below about 10 scale MPH.
Pat and I talked about it and, like with your Hudson, we decided the best course of action was a chassis swap, in this case a Lionel chassis from there Legacy version. Pete checked parts fitment and found the Lionel chassis was a drop in swap. Lionel used the same tooling as the K-Line Berkshire but put the motor in the firebox, as God intended. Same Pittman motor Pat is using in you Hudson. Pat had to machine a custom flywheel to fit but it all dropped right in after that.
No comparison. Rear facing motor chassis/large Pittman is a beast. You're gonna love it.
