if you're talking about removing JUST the mast, or actual antenna, you should see a flatted area right above the base, but before the actual antenna starts. It will take small open-end wrench; something like a 1/4"...don't remember for sure...see picture! <img src=http://www.duane.kennard.com/ant.jpg>
Of course, if yours isn't the same...again, this one is an '01.