I went out to the shop for 35 minutes this morning before going out to the weekly pilots' breakfast and got the downward bends and the twists in the front ends of both longerons. To verify George Orndorff's measurement of the downward bend, I laid a side skin down on the floor, laid a straight edge alongside, and measured it (photo 1). 2 - 3/4 inches just like George said it would be (photo 2).
Spreading the first longeron took quite a few iterations, but by the second one I had my arm calibrated, and it only took about 2 or 3 to get it right on. To make the twist I used a 10-inch adjustable wrench, and to measure it I used the inclinometer app on my iPad mini. After a few tries, I figured out it takes about 90 degrees of twist with the wrench to get the required 17 degrees of permanent set.
Like most other of the dreaded tasks so far, this longeron bending thing feels kind of anticlimactic now that it's done.
Setup for measuring the amount of downward bend.
2-3/4 inches, just like George Orndorff said it would be.