Thoughts on the "tender powered" engines.

Of course, one set of the unpowered driving wheels would have to be fitted with an appropriate gear and/or traction tyres to work as expected. Surely the motor could be removed from the powered tender's DU and moved to the loco instead of having to be from another source.

The TrackMaster RC Molly is loco drive despite being derived from a tender drive engine, though her proportions are (naturally) very different. Maybe the powered axle from it would be able to fit in a regular Molly somehow.