Backing Plates
I would not recommend using wood, as you would want the cleats to remain tight and secure, No?.. Do not defeat your work, expense, and or your original purpose.
I would use stainless steel plates, and or fender washers, with a decent thickness, ( as NoBozo had mentioned ), and all stainless steel hardware with nylock nuts...
Stainless steel will remain here, long after the rest of us! ( No Matter How Many Irene's Come Along )!
Terry
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