Nice work, Mel. Seems a shame to hide it away so far in the background, though.
Re: comments on the original's looks - could it be a 2ft gauge prototype that's been stretched to run on 3ft gauge, I wonder? Otherwise it woiuld seem to be suiutable for the US equivalent of a Feldbahn - if such things existed (plantation line, perhaps). I did have a picture of a greatly improved one, much modified by a member of my ex-model railway club, but can't find it. It does help to add a lot of clutter, towing chains or ropes, fuel drums, re-railing frogs etc. but the main fault is lack of width. HAving said that, certain small industrial diesels were dwarfed by the stock they were moving.
As regards performance, I bought an MDC chassis block from a friend and have used it under my freelance diesel switcher for about five years. With lots of lead inside the body it runs OK, but as it has no pick-up shoes the wheels (and track) need to be kept clean. Probably helps that it has always been an indoor locomotive.