Update on bolts - Gaffney advises that the heads of these bolts are spot welded by Winnebago. Since I see no thread changes, that suggests that the welds were broken during assembly and there is no access to the heads at this time. The amount of bolt showing suggest that the bolt head not only is loose, but also has pulled through from the top of some hidden beam to the bottom of that same beam.
My plan is to either loosen the nut or cut it off, then grip bolt from bottom and tighten as much as possible. My hope is that the aluminum beam will not allow head to pull completely out.
May be a while, as I will take my time. Have made last use of RV for the winter. I am in Central Florida and have daily access to my unit.
Thank All for your inputs.