Charles,
I had the same problem in our previous boat. The generator was out due to stringer replacement which is an entirley different story. I cut out the false floor over the V where the shaft ran then dug out the disgusting, stinking, saturated foam that filled the cavity. Once that was done I pulled the shaft, and pluged the opening at the rudder. Then made up a fitting so I could put air pressure on the tube to be sure it was the culprit. It was. If you use air pressure 4 lbs is plenty.
From there it was sazall time. I cut the tabbing and the big chunk of solid glass at the stuffing box. It was much easier than I thought it would be. I think it was also leaking where the aft part of the tube went through the hull because once I made the mentioned cuts it just lifted out.
The next step was a tube which I found after a google search at Nor Easter Yachts
Nor' Easter Yachts, Inc. - Custom Fiberglass Manufacturing - Milford, CT in Milford, CT less than a hour away. I had the yard glass it in as I wanted it to be in perfect alignment. Seaport Marine in Mystic, CT did a great job for me.
Photo 221 is the false floor cut away, foam (Did I say it was putrid?) dug out, shaft ready to remove. If you look close, you can see where the tabbing has been cut with the sawzall.
220 shows the whole shaft including the corroded fitting the stuffing box attaches to. That solid chunk the stuffing box fitting had to be removed as well.
230 Everything cut away and ready for the new tube. Not a good shot it was much cleaner than it looks.
228 The old tube. The leak is in the red circle.
226 fitting the stuffing box attached to.
Sorry to say I can not find a shot of the finished project. Will post if I do.
Good Luck,
Rob