mbryson might be able to give you some advice...
KILLER RIG by the way, that is way cool!!!
I get zero frame flex (or nearly zero) with my scrambler frame. It is plated down the entire inside, tied into the cage (6 points), plated down the outside of the front, and 2 additional cross members added. I was worried that there would be frame flex in the zone from behind the front leaf springs to the front of the cage...but it hasn't happened.
(outside looking under jeep)
Ok, the front of my cage is tied into the sliders, which tied into the frame in two places, one of which is directly behind the spring pocket and body mount (tied together). I guess that's why it doesn't flex there more than anywhere else.