Not good? Why not?
What were you told about the wiring? On my 1985, as on most C30's, the mast wiring enters the boat through the mast step. Some C30's, I believe the earlier models, had the wiring exit at the bottom of the mast, then enter the cabintop.Water does accumulate at the bottom of the inside of the mast after a rain, and it can and usually does follow the wiring tube down into the bilge. But changing this setup is a major endeavor (lots of time, work, or money), since it involves re-running all the wiring in the mast through the cabintop, along the roof of the cabin, down the side of the cabin, and to the electrical panel. Doing this and ending up with an attractive result is a bit of a challenge, I think.