Ok, I did a lot of reading and after marking up the longerons and cutting them to size I decided to use the socket and vise method to flare the end. I cut a 95.4 deg slot in some card stock and proceeded to squeeze away. I used a left over piece of angle to protect the corner and covered the socket with some duct tape as well as the jaws of the vice (new steel vice). The left over piece of angle had a arge fillet in the corner, so I filed it down until it was a sharpish corner, so it wouldn't mar the longeron too much. The flaring went fairly well, but the bending it back was more challenging than I expected. It's hard to get it back to flat, but I got there eventually. I started to try my hand at the bending, but I notice two things: first I was moving it about an inch for every whack, but I notice I was getting some waviness in the vertical leg of the angle (about every inch. So I started alternating to whack in-between my 1 inch marks, which helped a lot. Second I noticed a severe roll and drop of the angle as I started to get it bent. Then when I would straighten it back out, I notice I lost a lot of my bend. I decided to try using the bending die that I had read about. It should arrive in a few days. Meanwhile I'll proceed to the next step.
Cut to size and marked up the left and right longerons
Noted the start and end of each section to be bent or flared
