I think this will turn out to become one of those urban legends! A bass spends weeks underwater, comes out, is plugged in, and really works! Only an Alembic!
I would try to leave the bass as original as possible. Keep the scars.
The only thing I might add is that you should definitely take the advice of the people in the know here. I believe that with a combination of your personal ideas, and the expertise that Alembic has, that you will have an instrument that is amazing! Different from the original in some respects, but amazing, none the less!