Nearly there!
I had to take an afternoon off work to do the final fit - because it had been such a struggle. I pondered whether to fit 'end plates' to finish it off, but tried a cardboard template. It looks better 'bare' because it matches the wing edge. But it needed edging, so I referred to Baines' catalogue and selected a profile which matches the number plate box edging. The very last check was that there was clearance on full lock. So I jacked it up, and closed my eyes. There is something like 3/8inch clearance on lock. Perfick........ This picture shows the nearside on full lock.

And here, by special request (1560), here are some higher level pictures.



I hope you've enjoyed the story. It's been a real voyage of discovery, and at times, immensely frustrating.
And now.......

I must consider what to do next.