Thanks Glenn, Greg and Cory. Yes, the stencils and badges on the prop were hand painted, as was the entire prop and spinner. But the markings are really only tiny dots and strokes, to simulate the small writing.
Greg, check the style of roundels and squadron codes for the period depicted for your model, as there were three styles in use between 1942 and 1943 onwards. Of course, if you have a reference pic, that will help.