I do not know about your jeep but there are some possible ideas.
Mag mount, carefully GLUE a stainless steel circle to the center of the roof, mke it a 3' circle please.
I used to have a car where I wished not to drill holes,, I had enough clearance between hood and fender (I do not think you do but perhaps somewhere else) that I built a "Z" bracket.. Only make the bends in the "Z" right angles kind of like this
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Holes in the two flat parts. One was bolted to the fender, the antenna went in the other Hood went where the period is.
When I got rid of the car I removed and replaced the fender bolt, removing the bracket in the process. Bracket was painted to match the car (Dupli-color)
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