That's very similar to what I did. I have a 16' ladder strongback, and hung the hull from the shear at 4 points to level it and remove the twist. Alas, I couldn't sight up the rocker. It's very fair except this one spot. I'll try the fix this weekend and let y'all know how it goes.

>

> After wiring the panels together and measuring etc. to determine
> there was no twist, I hung weights (gallon jugs of water, etc.) from
> the wires which I left a bit long for this purpose. I adjusted the
> amount of weight along the keel until the rocker was smooth and fair.
> It worked quite well. To minimize flat spots at the bow and stern,
> my construction bench consisted of a pair of heavy 18' timbers with
> vertical 1x4 screwed to the sides at each end. I hung the hull from
> the 1x4 by clamping it at the shear clamps on each side. The whole
> deal is clamped to the horses with 4 bar clamps to allow easy adjustment.
> Later, I added a length of webbing between the 1x4 at each end to
> create a sling. This set up has worked extremely well.