Well, as of yesterday, you'll be glad (and relieved?) to know that the turrets are complete, and this will be my last post as regards progress on them. I've put together a final film, a mixture of stills and footage from within the turrets (with newly completed cupolas fitted).
So now the geodetic side of things begins, and I'll start a new thread eventually when there's progress to shew. Thanks for all your encouragement and interest.
Link: https://youtu.be/i3bkapxHp5M