I removed my galley in preparation to install a new muffler in an 89 Cat 30. The board that is below my galley and over my engine is not in the best of shape and appears to be masonite. Any ideas on what to use to replace? This area tends to get quite warm from the engine, so I would want something fire resisent, while being easy to clean (under the sinks). It would also have to be the exact thickness, as there is no margin when I re- install the galley unit.