Here is a question for the experts: I would like to install an opening port window in the aft berth of my H260. The best place would be as high as possible on the starboard side. This would put it about 30 inches above the water level. The manufcturer of the port claims its is waterproof even when submerged under water. I think it would be nice to be able to look outside or to get the cross ventilation but I don't want to ruin a perfectly good boat!