I woulds say it would be a good idea to increase the strength at any level just to prevent the problem if it wants to occur down the road. The upper battle boxes to me are a joke...I welded all around the entire seam on the bottom, I belive that would be stronger then the plate from behind and the couple stitch welds they use, but different strokes for different folks.
The lower system is a good idea I made my own from Stainless Stell so they will never rust, Some will say that Stainless is brittle but it all depends on what grade you use, I used a very hi-grade of stainless, they were a very good investment. I also revamped their design to give som additional support. I also made plates that go across the bottom of the box, like the Wolfe system this totally boxes them in to give even more strength. A set of sub-frame connectors would also go a long way good luck with the juice!
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