First of all, my welds are completely gone, all has become one Unfortunately, I was not able to control the distortion as well as I had hoped for (some was intentional). Some "libs" ended up distorting slightly more/less than others. No matter, I still have ye'olde O/A toarch!
I averaged 2.3 hammer-and-check cycles per "lib" against my jig to get them corrected. It was fairly simple, I just heated up the joint, and hammered on the opposite edge I wanted it to move (you can see my cheater-arrows)
They're not lying completely flat, and my macro lens is causing some distortion, but I promise, the "libs" of the F's are all lined up w/in probably 1/32 - 1/16 of eachother at the far ends. This is good enough, since I'm going to be trimming them roughly in half anyway.
Still workin' on how I'd like to mount the casters to the base platform. I can't weld them even if I wanted to, because they all have grease-fittings and bearings that would get cooked.
So some kind of adapter-plate and stubby-little extension legs are called for. Just not sure if I should use 1-in angle-iron stumps (three per corner) or spring for some 3 or 4-in square-tubing...that I'd then need to cut down :S
Leaning toward the angle-iron just for the ease-of-cutting factor.