We have a "Boater's World" here and they have the plugs and gaskets you need. For a better fit from a screwdriver, get the largest one you can find (Sears, etc.) and maybe put it on a grinder till the thickness better fits. But, if you put the new one in right, I don't think you would have to worry about it. The old one may have been screwed in so tight trying to stop a leak that a .15 gasket would have fixed.


Dan