Here she is at close of play today. We had hoped to rove up the frames before knocking off for Easter and may slip down to the shed tomorrow and finish the job for (as Mattis says) we can't possibly work on Easter Sunday.
Fitting the top section of the frames entailed quite a bit of juggling of templates and angles. Needless to say Mattis and I had totally different ways of achieving the same result, and they took about the same amount of time. I relied on templates, cutting the frames at the wide side and by measuring the gaps, could transfer the measurements to the aft (shy) side, which was then beveled on the band saw.
Easier done than said (or maybe vice versa). Mattis used templates, and a bevel gauge, using saw cuts to transfer the bevel to the faces meeting the strakes. The bevel gauge neatly slots into the saw cuts from face to face. It's a technique I may have invented myself. But probably age old.
Happy Easter to all who stumble upon this, and especially to my 47 followers. Bless you!