Hi Garry,
The sides are one plate, but in a 3d model when baked and has textures no one will tell I built it as two meshes, the reason why I built it like that is so I can throw the timber built cabs on it for a later version without the need to build and map a new side plate.
The Loco was built by Beyer Peacock 1878 and entered service as a Pattern engine from 1879, Phoenix Foundry Ballarat built copies from 1881 to 1883, they where known as heavy goods 0-6-0 at the time and where named Bulldogs, don't know why they where known as heavy 0-6-0's when the O Class from 1860's has a heavier axle load, in 1886 the Victorian Railways started to assign a letter to each kind of loco as their pulling power and axle loads where all different, they became R Class, around the same time another loco built from Belgian with similar stats where also known as R Class, then from 1889 another R Class was built from a design Kitson & Co, Leeds draw-ed up and became New R, then in 1951 another R Class was built and the remaining New R Class where re-classed to Y Class.
Their where 4 variations to the R Class, the Beyer Peacock R class was scrapped in 1924, and the very last one was withdrawn 1944 and scrapped sometime after it, preservation didn't start till mid 1950's so their where a few locos lost that where withdrawn between 1940-1950.
Cheers.