I'm looking to possibly replace the leak prone, problematic gas cap unit with a Mocal, aero-type filler cap. Has anyone done so, or found another alternative filler cap system that won't collect a pool of water that then leaks into the trunk and onto the gas tank, with resulting rust. The cap I'm looking at is available from BAT Inc., in Sarasota, Florida, and is the Aero 300 with intregal funnel. Any suggestions? Opinions? Thanks kindly, Norm Vandal