I own a 1985 Hunter 31 and need to replace the front hatch. Unfortunately it was open and a jib sheet caught it while coming about and "tweaked" the hinges. It closes and stays dry, but I can't open it easily and keep it open. I don't see any markings indicating a manufacturer, and no exposed fasteners. Not exactl sure how to take this one one. The hatch glass measures approx 21" square.