Two Cylinder Vertical Engine for 16 wheeler

This engine approximates the prime mover of the Johnston 16 Wheeler, a truly fantastical geared locomotive manufactured by  J. Johnston and Sons in New Zealand in the early 20th century.  The Locomotive has 16 drivers in four trucks for use on light rail. The engine is a unique dual design and features a three speed transmission incorporated in its base. This presumably overcame the speed limitations of North American geared locomotives.
This locomotive is worth looking up because it illustrates how isolation can lead to a totally different approach.
The engine measures 80" from the underside of the base to the top of the cylinder head in S scale (1/64).