I was under the impression that these things bolt on. I remember reading on one of the forums about somebody needing to adjust them up due to insufficient ground clearance in the retracted position ( from the factory!).
I haven't researched as much as you have from the looks of it. I do have an email out yo HWH asking how much weight it'll add and which system I need.
Anyway, have you looked at HWH? I look forward to reading your impressions after the factory visit. Pls post it!
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