Best I can pass on from the tech: There are two main I-beams running the length of the camper. The pan is attached with pneumatically punched fasteners, around the outside edges. The cross braces are smaller(6") and level with the top of the 10"ers. There is nothing down the center of the camper to attach the pan to, except in the axle area. This explains ours sagging front and rear center.
Hope y'all understand this. And, the only way to remove these fasteners is to cut them off, grinder, metabo, or a hammer + chisel.
David & Kelly
2015 Sandpiper 355RE
2015 Silverado 3500 CCSB SRW 4X4 D-maxx
Nights camped in 2016:03😄