Lumpy,

There was no V Corps in Vietnam, I Corps was the Northern Corps, IV Corps was the Delta area on the Southern tip of Vietnam..

With your confusion and being that you are located 50 miles South of civilization, I assumed the location of your service in Vietnam was in V Corps, which would be South of IV Corps, which would mean in the water that was South of Vietnam. And it is pretty deep out there (the water that is)
Huey