I tossed around a few ideas as to how best have the filler protrude through the fabric. Cut a 0.8mm plywood template and then jigsawed a hole in the middle slightly larger than the filer neck. Applied the Hotmelt cut the fabric so it could be glued to the under side of the template. Applied heat to set the adhesion and then placed it over the filler neck. Have now heat shrunk the Oratex on the upper surface of the wing with just the ends to finish off. Am deciding the best way to weather proof the gap between the filler neck and the hole in the fabric. Most likely a bead of silicone.