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I personally would try something in this family secured from underneath maybe even mounted to a larger plate or some fiberglass patch underneat, could get a sheet of thin baltic birch glued down first as a doubler from underneath as well. Can get this at hobby lobby or similar. Id fill the top with Bondo and do cosmetic touch up. This will hold up

https://www.mcmaster.com/products/threaded-inserts/screw-mount-nuts-2~/

https://www.mcmaster.com/products/threaded-inserts/adhesive-mount-nuts-2~/