I've worked in spurts the last few days. I marked off the various lengths on the longerons that show where the main fuselage bend starts and ends, and I made some marks every inch inside the bend area just to help bend with consistency.
Van's method is to simply put the longeron in the vice, bend it a bit, then whack it with a mallet to set the bend - over and over and over. I've been told by many that this is easier said than done, so I'm trying a different technique. I took 3 stacks of 2 nickels and taped them to the vice. Two stacks on one side and one stack in the middle of the other side. By cranking down lightly on the vice, it puts a bend in the longeron. No hammer necessary. The main problem is that by putting a bend in the horizontal direction, the angle inherently also bends in the vertical direction. Once you flip the longeron 90 degrees to take out the vertical bend, it also moves the horizontal bend again, so there is a ton of back and forth and back and forth. I still haven't quite gotten the horizontal bend correct because of that. Van's says both dimensions need to be within 1/16" (horizontal 1/16" within the template line and the vertical component laying flat on a table within 1/16").
Van's provides a paper template for the curve, but for a big part of it you can actually test it against the actual curved rail cap that it'll be riveted to (more accurate than the paper template).
I'll come back to bending later. It's one of those things that is better to do in small chunks so the frustration of two steps forward one step backwards doesn't become too much.
Van's finally sent the right rivets and material that I was missing for the center bulkhead, so I jumped back to that to finish it off. I made the spacers that go on the back of the fore bulkhead, primed, riveted nut plates on, and riveted the whole thing to the bulkhead.
With the spacer on, I could screw on the remaining two outside ribs to the front side of the bulkhead.
The last step for these bulkheads was to temporarily bolt them together to check that everything lines up, before taking it all apart and storing it for later. I made some wood spacers that perfectly (as perfect as I could get wood to be anyway) fit in between the bulkheads, taking up the space that will ultimately be filled by the wing spars. I bought some bolts at Home Depot to line the holes up. The final bolts that are used are close tolerance bolts. They are extremely difficult to get in, so aren't used until the wings are ready for the final mounting. Apparently you often have to shrink the bolts by freezing them, otherwise they are difficult to fit. The hardware store bolts are slightly smaller, so slide right in. I also checked that the two long bolts on the inside fit (you can see them just outside of the control rod bases). I had to drill a reference hole to 1/4". I'm not sure if I got that just slightly off or what, because one of the bolts was a nightmare to get in. I finally got everything together by doing them all little by little. So in the end it all fits okay. I dismantled everything, bagged the bolts and spacers for later, and stored the bulkheads.
