Thanks to all who responded.
For those that might have missed it the answer is:
tr = g(h-a)
tr = allowable turning radius
g = distance from the tower base to the anchor of the guy
wire you are trying to clear.
h = height on the tower where the guy wire you are trying to
a = antenna height
100 foot tower, two sets of guy wires anchored 80' from base.
You are trying to clear the top guy, which is at the 100' level,
for an antenna at 51 foot height.
tr = 80 (100 - 51)
tr = 39.2' allowable turning radius
You can also make a scaled drawing. I tried both.
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