It's a 2013 Kodiak 242RESL with an aluminum i-beam. The fifth wheel is a 2016 Wildcat 295rsx with a BAL frame. The Wildcat came with the factory provided fold-up storage deck at the back. That deck is attached to frame extensions and is rated at 300 pounds.
My GearDeck's cargo box is 25#, the receiver frame is 50# but for the fifth wheel I will just be attaching the cargo box to the factory foldup deck. My generator weighs 86# and my grill weighs 23#. Sometimes I put gas cans in there and an occasional folding chair or two. With 17 cubic feet of storage, I never get over a couple of hundred pounds.
Gear Deck 17 Tech Specs
Check out the youtube video above. Also, I can't stress enough how important a good welder and fabricator was for me. I never used the bumper but I probably could have after he got thru finishing what the factory should have done. By the way, this is an expensive solution GearDeck17 $1100 plus fabricate/weld $350.