I have a new old stock one for a yanmar 4JHE looks the same but not sure of tach setting or wireing. I also have a used 3GM30 F yanmar panel with tach buzzer and warning lights round plugs. Working take out has a slight crack in frame. If interested can sent photo.
That derelict boat was another dream for somebody else, don't let it be your nightmare and a waste of your life.