We were a fleetwood dealer and had to repair several stepwell boxes. It is a simple repair and easily done by anyone with simple carpentry skills. I always went back without the metal cover. I felt it held the moisture in and caused most of the problem. I always primed the box and sprayed with several coats of undercoating.
1998 Pace Arrow 35 ft. F53 Ford V10 2014 Honda CRV toad
32 years mechanic at Delta Air Lines 15 year motorhome service manager. 3 popups....2 travel trailers....5 motorhomes....loved them all.