Hello all! We recently bought a used Catalina 25. On board we found a Windscoop, but I have no idea exactly how to attach it to a hatch for ventilation. It's like the one linked below. It includes three dowel rods, each about 20" long, and each having a small open hook near each end. I know you hoist the top end by a line off the mast, but I can't figure out how to secure it to the hatch.Web searchs found plenty of sites selling the Windscoop, but no info on how to use it. Anyone have a link to instructions, or could describe how this scoop is used?Thanks!Jack