Thanks J found your GrabCad files, nice. From there I determined it was a Westbury design so I probably got the castings from Woking unfortunately long gone. Possible that Hemingway has some info but I do not deal with him. On examine the transfer passage is already done in the casting so that is good. The sleeves are installed but not drilled so will have to figure that out. In addition the crank has not been drilled and there is no rotary valve. There is a mention of the engine in Westbury's book but no drawings
Bob