My sailing guru Trey Brown got me straight this am. The length of the sock and where the bridles are determines where to install the hoop. He also suggested the hoop not be at 90 degrees to the pole but angled or canted toward the bridle tang. Mounted on port side. Line attached to pole, thru slot in hoop and tied to bridle tang to support hoop and prevent tangle with sheet lines. Anyone got more to add?