I don't know anything about the black cranks, sorry. They are said to be wartime production; I don't know.
We need to hear from Mark, aka sciencemonster, preferably with more photos of
his '45 Rudge.
According to
Martin Hanczyc, your trigger shifter is Model GC3, made 1938 - 1948.
Flickr user Grubb1937 gas a great photostream that includes a photo of a '51 Nottingham Rudge:
