Hello Paul,
Yes I have one,
I have just acquired a 1967 B40, its been sitting for a long time, water in everything, seized but this was the clutch rather than engine, i have already make a lot of progress, my aim is to get it running and registered without doing any cosmetics like cleaning etc.
As far as i can see its all pretty original but unfortunately someone in the past has hand painted the whole bike in a lighter green, but this paint is flaking off revealing the original darker green underneath, I figure this adds to the history.