I found this worth mentioning because people were having antenna corrosion problems in another forum.
Go to http://www.avdec.com. They sell conductive antenna gel gaskets that not only bond really well but protect your antenna and airframe from corrosion or water intrusion. Install these, seal the screw holes with rtv, and your done. The edges will look a little funny after time but if you ever change or remove your antenna it will look brand new underneath. I do not represent Av-dec but have used them for years, they have a lot of gaskets with different footprints. If they don’t have the correct one you can get a large ADF gasket and cut them to fit. Give them a call.
One less problem to worry about!!!