Not sure what you mean by up front by the coupling. There isn't anything to support until you go back under where the pump clamps to the hull. That area you can only use a piece so big or it won't fit, and then you have to use two pieces that size inserting them into that area one from each side, then stack them so their combined thickness provides the needed support. Then I skin the inside of the hull area that I can reach with polyurethane, and fill the rest of the void under the pump with expanding foam to further solidify the back of the hull.
