Welcome aboard CF.
That's a project
boat for sure!
Is there no evidence on the outside of the hull
as to where the chainplates were attached? If you can find them, you can probably work
out the mast
height by making a scale drawing, then projecting the mast
up perpendicular to the earth, then the length of the side wire to the chain plate
, and voila, you have two congruent triangles, and given the lengths, can work our the degrees of the included angles, and so forth. It's high school
geometry, and you can do it. However, let's hope someone comes along and can just give you the numbers, it'll be easier, but given some scrap paper, you can work out most of what you need, I think. [Using graph paper to make scale drawings has helped me on many projects.] Anybody out there should feel free to point out where i have gone wrong, if I have.