It was taken at work near Oxford - just commuting in honour of D-Day - although the previous owner had taken it to Normandy more than once.
Regarding the field stand lug, please see pictures attached.
someone may have more accurate dimensions but:
The curved section brazed to the frames is 1 1/2 inches long
The stem from the frame to the flange is 1 inch
The flange is 1/4 inch thick x 1 3/4 wide
Note the cut away in the flange to stop the hinge rotating too far when in use
The threaded part of the stud is 3/8"
The hinged part is fairly straight forward as you can see from the photos apart from the stop shown in the pic from below

- Lug - from below

- Lug - from front

- Lug - from end