Well the new tank I bought off of Ebay is about 3/4" of inch too wide for the opening in the deck. So I cut the floor 3/4" all the way around the opening. I'm going to seal the edges of the exposed wood with West epoxy. I think I'm going to get galvanized joist hangers and attach them 4 of them per side to the two stringers and run 2x4's accross the span to support the Seaboard panel I'm ordering. I think it should work, its just like every job you think is going to be easy turns into a nightmare.