I admire Lionel's engineers. I put the motor in the firebox on mine, and it was not an easy task. I suppose it would have been easier if I had just sawed the back end of the frame off and started over with fresh metal.
K-Line, in my opinion, committed sacrilege with their U-shaped boilers and motors over the cylinders. Sawing off those skirts and replacing them with round was likewise not an easy task. The rest of their Berk/Hudson models were very well done.