I'm doing the same thing. I have a
1960 Tradewind. It obviously had multiple leaks. the first thing I did was re-gasket every opening and fix the roof vents. I am in the process of removing all the interior cabinetry and gallery (tomorrow is galley removal day). I am photographing each thing I remove and diagram where everything goes. I have to replace a large amount of the floor and who knows how much plumbing. I asked about a professional doing the job and the only answer I got was "Oh wow, this is going to be very expensive." Then they laughed.