should be easy so long as you can get the dimensions of one of the carriages you can just measure the wheel diamater against the carriage length or height in the illustration a figure out the measurements to a suitable unit scale.
Not sure what the problem is. Plenty of good reference material for an artist to figure it out in the links above.
You might be able to find a scale 3d model, even if its commercial you can still use it to trace a quick mass object as a reference for your own model.
Not sure what the problem is. Plenty of good reference material for an artist to figure it out in the links above.
You might be able to find a scale 3d model, even if its commercial you can still use it to trace a quick mass object as a reference for your own model.