I found a $13 gasket that was made for a VW but fits well on our Crossfires and is easy to install without having to remove the tailight and antenna base. First, use painters tape to mask area around base. Then use an exacto knife to cut away old gasket. Some of the gasket will be under base so that will need to be removed too. Once you have it removed use some adhesive cleaner to clean. Apply some silicone between fender and antenna and a bead on bottom of gasket. Fix gasket to narrower side and stretch to front making sure the edge goes between fender and base. Press down on gasket. Clean any silicone that squeezes out. Tape front of gasket to allow sealant to harden with front of gasket tight against fender. Allow to dry for 24 hours. Clean any excess silicone. (Step not done, use black trim conditioner on the base plastic).

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