[SIKSUKR]

Originally Posted by trfour

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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I would use both.Plywood on the fiberglass surface with a steel plate on top of that.