That starter motor near most in the last picture is exactly the same as the starters we had in the Twin Pioneer aircraft we restored 15 years ago, these with Alvis Leonides 9 cylinder radial engines. You can see by the mounting flange that it will bolt on in many different positions. The control panel even has a Bowden twin lever control, I can only assume one lever for the choke and one for the throttle...? I wonder what their take on a "Uniflow" engine meant....Reminds me of an old Commer Knocker engine, except they had a supercharger, being a 2 stroke design.