I kept the longerons unbent and out of the way until they were needed. I was nervous about bending them but was a little more at ease once I saw they weren't as thick as I had thought.
Started by moving the vise to the center of the garage so I could fit the longerons in. Was super carfeul to measure twice, mark, mark top/side forward/aft, etc. I cut a couple pieces of scrap angle and wrapped them in electrical tape to hold the angle in the vise. The I clamped the angle in the vise and used two c-clamps to clamp down the angle to minimize twisting while I bent it. I had an electronic protracter but I found it wasn't too useful.
Started by positioning the left longeron end where it should be, then gave it a giant whack with the rubber mallet top and side. To do the measurement, I clamped a 4 foot piece of steel angle (doesn't sag) on top of the longeron and then measured from it. I was able to get the 2.75" and 1" front bend pretty easily.
Likewise, I was able to get the aft 5" bend fairly quickly.
