Before you yank on it....
The original muffler on the 80's vintage Hunter 30 was a Stainless Steel, water-lock muffler with a 2" inlet and outlet. The SS muffler is no longer manufactured, but a Primex fiberglass replacement can be purchased from Marine Mufflers, part Number-MC2. Call 407-886-1144, or West Marine, or just contact Hunter Marine. I replaced the entire exhaust system (mixing elbow, engine hose, muffler, exhaust hose) a few years back. If you disconnect the exhaust hose from the thru hull and the engine hose from the mixing elbow, you can yank the whole thing (forward and over the engine) out from under the fuel tank and battery shelf. Yup! the muffler just sits there next to that piece of wood. The hoses are probably hard as a rock by now so you might as well change them. Be sure to mount the new muffler according to the "This side up" instructions and double clamp everything.