I have a 16ft Polarkraft jon. It was originally a 20" transom. The previous owner notched out the transom to make it 15". I want to rebuild it back to the 20". What is the best way to do this?? I can have a piece fabricated to fit over the notch. How do you get the plywood to fasten in securely to the wood that has been notched? A friend said that the new piece should be bolted on instead of welded because it gets too hot when welded, and would burn he wood under the aluminum and it would rot it out. Is this true?? Thanks