You can also get repair antennas. They fit over the nub of the old one, and use a small Allen bolt to secure.
Check the " HELP" section of the auto parts store.

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Remove radio to get at antenna cable. You may be able to saw off existing antenna stub, or simply unscrew it to release it. Taking the outside remaining end of the antenna cable, securely tie or wire the plug end of the replace ment antenna cable to the existing cable's cut off end. Then wrap the attachment point with masking tape so this doesn't snag on anything when you feed in the new cable. Getting back inside, get the old cable and pull on it. This will snake the new cable into place. Attach that to the radio. re-install radio. from outside insert new connected antenna base hardware into body hole and then screw down the bezel to get a secure firm tight fit. (you need the kind that can be secured from outside).

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