Re: 86 Mariner 210
J & M, Why not just use some wider peices of aluminum like the ones that came stock in the LL. Say around 4" or so. If you lay them over the sheet foam you wouldn't need the wood. I just hate to see the wood getting buried down there to rot over time. I went back with only 1/2" ply over the foam and the strips and the floor is rock solid. Does your 86 have 3/4" ply like mine does?