[BusNit]

I cut out the worst portions of the metal and used a grinder to remove the surface rust from the main runners. The main runners are in excellent condition considering the amount of rot. I found evidence of some kind of OSB wood that was used which had some kind of clear coat. Only the clear coat remained and is stuck to the bottom of the water bay liner fiberglass. I found no other wood as it had so disintegrated. I put in a pre-cut galvanized sheet which will get welded as a filler. Not sure what to use as a 1/2" gap filler where the wood once was. I may put sections of 1/2" angle welded on edge. Still deciding on that. (An air gap would be excellent for any possible future water leaks)