I have a portable gasoline generator that had a mechanical linkage to the gas gauge. Over the years the linkage pivots (plastic) softened and failed. The "meter" no longer snaps in the approximately 1 inch hole on the top of the tank. Without the ability to reach the back of the gauge, I can't tighten it, and gas leaks when I move the generator. Since I can live without the gauge, I bedded it with 3M 5200 bedding compound - that promptly softened and continued to leak. Any thoughts on how I can seal it? Generac 4000EXL