Remove a couple of hose clamps and about four feet of flexible hose and your done. Technically the drain is above the water line, but if you want to be sure the boat is not squatting then empty the aft water tank.
Should be an easy fix providing you can fit into the starboard lazzerat. Aka dungeon.
The top clamps are no problem but accessing the aft thru-hull is a job for someone small and flexible.. The ribbed white (ish) hose is the cockpit drain and it ends WAY back there by the transom in the depths of the "pit"
I am looking at needing to do the same job this week to replace 35+-year-old hoses that look like wire-reinforced vacuum cleaner hoses. I am wondering what folks used as a replacement hose. Recommendations?