I took a look at one online. The base plate is screwed into the roof. The antenna then screws into the base plate with a locking washer on the back side. I was able to tighten and loosen it just by spinning it. If it is real loose, just spin it clockwise to tighten, if the seal breaks, reseal. However I think the caulk will hold it where it is and you shouldn't have to do anything. If its pointing to the tail end I don't see it causing any issues.
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