Welcome to the forum.
Congrats on finding a piece of sailboat history.
There were 24 Mystic 30 boats built between 1978 and 1982. Since that time the company has changed interest and is now supporting the USNavy with their submarines.
Peter (the designer of your boat) maybe stil working with the company.
here is contact information I found.
860.446.8058
lbiadmin@lbicorp.com
message us
973 North Road
Groton, CT 06340
They may have some old drawings of your boat in a storage room.
Otherwise your going to need to become your own designer and make the changes to suit your interests.
In making changes, I have been doing that on my boat, you need to consider the whole system. For example with the black water tank.
You want it in a place that is about the same height as the head. You want to run the effluent line from the head to the tank in such a way that you pump up vertically (less than 3.5 feet) and run in a gradual downward slope to the tank. I think the slope is about 5 degrees. This allows the pump to move your deposits upward and the fluid to flow with gravity to the tank.
All this is dependent on your boat space and your skills to solve problems. Exciting, no!
