A quick Google search reveals the following helpful post to TowerTalk back in
Y2K. If memory serves, K7LXC has mentioned the 3" per 100 feet spec before on
18.104.22.168 plumb - For guyed structures, the maximum deviation from the true
vertical shall be one part in 400, (3 in. per 100 ft).
For self-supporting structures, the maximum deviation from true vertical shall
be one part in 250, (4.8 in. per 100 ft).
If it were my tower I'd try to get the tower a lot straighter than a foot off.
I'd also adjust the positions of the preforms and turnbuckles now to allow easy
tensioning and adjustment down the road.
As written in the query he's just adjusting for plumb. Since this sounds like
his first big tower you might remind him to adjust for appropriate guy wire
tension too (Loos gauge, etc, etc).
Hope that helps. I spent the better part of a morning adjusting the guy wires
on my 55G tower to get it straight and pretensioned properly. Could have gone
faster with some additional hands, but took my time, was patient and it went