Why bother on 'Me-509'?? It was never built, not even as a mock-up and the project was already cancelled at a very early stage when detailed design drawings were not even made.
With most of the Messerschmitt archives destroyed during Allied air raids a lot of detail on that 'Me-509' kit is just speculation. The earlier Me-309 did at least fly as a prototype and I personally would welcome a nice 1:48 kit from the same manufacturer of this type instead of that would-be project!!