Barry, hi!
Your question is  little imprecise. If you only wnt to know how much
tension to place on the shroud, here is: as you take from on side to the
other, there should be no slack in the lee shrouds. If there is, take up
a little on the turnbuckles and then tack. If there is again a little
slack, take up on the lee t/b. Repeat until there is no slack left.
Do this in a fair breeze, at +/- 18/20 knots.
Agreed that this will not give you the answer to mast rake etc.etc. That
is what I mean by your question being fuzzy. This will only answer the
"tension" question. Now the stay and backstay are a different kettle of
fish. They govern sail sahpe and I do not know the sloop you are on...
May you have beam winds...
___ Blue Wave/QWK v2.12
--- Maximus/2 2.02
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