I also vote for Gerry's Beam Engine. Probably running on air rather than steam but doesn't matter to me.
I would like to put in at this time a request that I make the side frames. Machining upwards to 8 sets would be difficult to accomplish manually so this would be perfect for CNC. I still would be willing to make other parts depending what was needed ... CNC or not.
The drawings that I have downloaded do not give all the dimensions (non critical ones are missing), so I will be looking for those elsewhere.
Also, these drawing also do not provide a base ... so that will have looked in to.
Other items may be missing so a good drawing review is needed.
I will using Solidworks for my drawing then convert to g-code.