Quote Originally Posted by PaulR View Post
Page 38 - I think the photos are of a 3rd Series MK 11 (the sight is in the middle). Sorry I could be wrong.

Even if I am right it is a superb reference work.
The sight shown on P.38, is the second pattern aperture sight as fitted to the third series Mk.II Service.
The bottom descriptions could confuse, but the top right description is clear.