In my preps for the superflexy, I removed what was in those arches, nothing but plastic, the rest is hollow. I imagine he had some major cutting at the front part of the body seam though, and cut the lip off of the cladding, there is nothing under there either, just the tabs that the splash guards mount to. The rear on the other hand...I hope he doesn't have any plans of maintaining the two feet of wheel travel, I already rub, and his tires are 6" bigger than mine!!!