Hi there Tim
The strip, I believe, on the plan is referring to the rubbing/fender strip which runs around at deck level on the tug.
The height of the frames should be in the middle of this strip width. Therefore when you add the bulwarks and decking you then apply the rubbing strip which hides the joint between the bulwarks and planking.
The angle or the radius on top of the frames is the camber and there is a correct formula for calculating the height of this – to which I will have to look this up to refresh one’s senile memory (getting old you know) . I do believe there is a centre height drawn on the profile plan if you have a look – it gives you a height to the centre of the deck (I am sure).
Sorry I cannot be more help, because I gave the plans away to someone on the forum – so I am having to go back to the build and scrutinize from there.
Anymore queries, please don’t hesitate – AND PUT SOME PICS OF YOUR BUILD ON

aye
john