There does appear to be a double bend in this photo and in the one you posted from underneath.
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The torque boxes are not level on a TJ, so you need a spacer on the higher one to bridge the gap. There appears to be something in that area in this photo, but it’s unclear what it is.
View attachment 397735
Their description says they tie into the body mounts, which is a bad idea. Let the body mounts do what they do, and don’t put another function on them.
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It’s unclear if they are ww2ww due to the other mods like HiLine on that test fit rig. I doubt it. There are not enough mounting points into the torque boxes, so aim for altering the bottom to stay away from the body mounts and tie into the torque boxes. No mention of backing plates. You can probably fix everything but the ww2ww, but is it worth it?
That looks like a spacer welded with 2 holes in it. I recall it is not much height difference between the rocker boxes. I think was like 3/16”. I modified my PS guards to get them off the body mounts and onto the rocker boxes.