Yes, you do have to remove the fender skirt. There is an "L" bracket at the bottom of the antenna bracket. It is bolted to the engine compartment apron. I'm sure that 10mm bolt is loose.
Do yourself a favor and pick up a bunch of the plastic grommet(the same ones used to run the screws in that hold the liscence plate on) and a bunch of the same screws. Any auto parts store has these. You will break a bunch of the connectors that hold on the apron.
I always toss the originals becase the screw and grommet methode works a hell of a lot easier and it is easyier to remove the skirt in the future.
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