Hello.
I remember some previous thread about this topic.
I just bought an early (WM20 7805) engine and it has remains of silver paint on crankcases. It is quite corroded and wount turn but have good barrel with standard bore. Piston has number 66-1024 on top.
I believe it has seen no use after war. Kalle

Hi Kalle, It does appear some early M20s got the silver paint treatment on the crankcases. All the ones described so far with paint remnants have been from this early period.
It would be interesting to know whether the gearboxes were similarly finished and when this practice ended..Ian

email (option): julie@wright52.plus.com