: Great looking boat Elliot !
: Thanks for the help,
: Ian

Ian,
When I built the ES I used an aluminum strongback which was dead-on straight and stayed that way. One thing I did that has not been mentioned yet, that might help:
Make a a tiny saw cut exactly on every reference line at the outside edge of each form. This saw cut is best done with a very fine pull saw and only needs to be 1/32" or so deep. After you have everything aligned by eye using the reference lines, lay a fine sewing thread from bow to stern along each reference line. Stretch the threads into the tiny saw cuts which keeps them on the reference lines. Install these threads from sheer to sheer at every reference line just like they were strips.
Now when you look down the forms, it will be easy to see what forms are not in perfect alignment.

Good luck,

Larry C.