Inspired by Lord Legoman and his British Rail class 47, (see it here: www.flickr.com/photos/lordlegoman/16508777851/in/faves-55... ) I have built a sort-of copy. He didn't upload more than one picture, so I guessed on the front / rear panels and innards. The model was originally a Class 47, but I changed some parts of the model and renumbered it into the solitary Class 53, which was named "Falcon" in real life... and from what I can tell, it was really painted in a livery related to this lime green one before being scrapped in 1975.
This is the real life History of class 53: (courtesy of Wikipedia)
British Rail assigned Class 53 to the single Brush Traction-built prototype locomotive Falcon. While not in any sense a failure, the design was the victim of advances in locomotive technology (specifically, the power obtainable from single low-speed diesel engines) and was never duplicated. It was scrapped in 1975, less than 15 years after number 1200 was built in 1961.
The loco should have the number 1200 on the left / right sides of the loco where the four studs are exposed, and the name FALCON where the six lime green studs are on each side. All of these should be in printed 1 x 1 tiles.