I'm looking a buying a F350 SRW supercab longbed for 5th wheel towing.

I want to put a low profile chest type box behind the cab and cover it with a fold-up bed cover (Advantage I think). In doing this, I see the need for steps forward of the rear wheelwells in order to reach down into the box from the sides.

I have not found any aftermarket tubes that run from the rear wheel and also cover the cab for this truck. The alternative might be an additional shorter bar just for the bed area that covers from the wells forward to the back of the cab.

I particularly do not want fiberglass or diamond plate "shelves", I want tubes! And I prefer to match Ford OEM tubes if possible.

Any help or advice putting this together much appreciated!