Just grind down and feather out from the repair area, then take a couple of pieces of scrap wood, contoured to the shape of the hull lip, wrap it in plastic wrap and clamp it on.
Get some resin and cloth (maybe chopped strand or woven roven), and build up the area, cupped by the clamped wood and reform it. Remove the jig, Grind, sand ,and fair the area and finish to ur liking.
Edit: I would do the repair with epoxy resin......
