Well "Sundayflyer32", I don't know why those other folks are ripping that post assembly apart. Unless the post is rotten, I can't see any reason to replace it. (even if split I'd install carriage bolts through it...) Also, I can't see how replacing it will address the source of the problem, i.e., the poorly supported, under-strength, doomed to be crushed plywood cabin sole.
BTW, that is not Bob Perry's problem but is Islander's engineering interpretation of his design.
PS, On our boat, the Ground cable and mast electrical leads run down the starboard side of the post covered by a piece of wood trim. pc