I have been rather busy in the workshop over the weekend…
I now have a Simplex. Few bugs to iron out….
Axle pump made, fitted and working.
The Cylinder Drains were, um, well open or open or sometimes closed….
Attempt 1 at 'automatic' drains resulted in Closed, Closed or Closed (and a nice oily Shower).
This is my next attempt.

They will be Steam Operated using a PTFE diaphragm to close the holes in the top.
Still a bit of work and cleaning to do and the correct screws are on order.
Valve seems to work, will see when I get it all connected up.