We set up on the shoreline at +2866 x -4149 x 308 and pulled to just off the shoreline shelf in the water.
The sharks have horrid pathing issues especially with the z axis, where they can hit you, but you cannot hit them.
You almost have to fight them under the water for melee, but spell casting will land on them from the shore, as well as heals on your tank.
Be careful about pulling them too close to the shoreline, if they get in the shallows, not only will they get stuck, but your tanks will have targetting issues with the whole "in the water" versus "out of the water" problem.
+3553 x -3996 x 296 is an approximate shark spawn point. This is your safest bet with the fewest or least chance of adds.
If you are doing this quest for a single player or a duo, this is not too bad, sometimes they will chain spawn, sometimes will take up to 10-15 minutes to spawn.
If you are doing it for a full group ..... well pack a lunch, you are going to be here a while.
Reefrunner (yellow con at level 76) spawned close to the above listed /loc easy pull and kill, dropped the Salt Encrusted Cloak.
IMO all other shark spawn points in or around the ship wrecks just were not worth the fustration or effort (not to mention skelly adds). So far this has been the worst part of this quest and I wish the Devs would looking into unsticking the stuck sharks, fixing the pathing of the others, and all around general hard look at the coding for these mobs.
Good luck, hope this was helpful to someone.