I had a sheared bolt also (two really which almost pitched my wife headfirst to the ground when the second one sheared
). The bolt heads were captured at the top so the nuts could be removed. One of them wanted to spin as I removed the nut so I had to put a screwdriver between the bracket and the metal above to keep the nut in the capture zone. That let me remove the assembly so I could get to the sheared bolts.
After I got the sheared bolts out I found that the blind holes in the housing the bolts went into were not threaded deep enough. That left some slop and I think is why the bolts sheared. I ended up putting some washers under the heads of the replacement bolts so they would really tighten up the stairs.
They are solid now and and much better than when we bought the coach new.
Clay WA5NMR - Ex Snowbird - 1 year, Ex Full timer for 11 years - 2004 Winnebago Sightseer 35N Workhorse chassis. Honda Accord toad.