John,
Thank you for your insight. I wonder if replacing the trailing truck with a truck-mounted coupler will help. I am not skilled enough to mess with reshaping high dollar models. Are you aware of other On30 locomotives appropriate for my 15" situation?
Greg

Regarding the FORNEY loco, how much does the trailing truck move side-to-side? I know Bachmann says 18" is the minimum radius, but I can use this unit on my 15" radius if pony and trailing trucks are allowed to follow the track.
Thank you, your opinions will be invaluable.