What excellent photos, thanks for posting them! I suppose it's a given that rotary engines were messy things and many of the photos will help take some of the guesswork out of realistic finishes. However, The shot of the rear starboard horizontal surface on the inline powered SE5a intrigues me. What has happened to the "skin"? Is it muck, or I wonder, has the heat from a long exhaust caused damage? Or is it something entirely different?
Best wishes
Nigel.