Greigers-Gen 1

Hey guys,

I want to remove the antenna on my car and replace it with one that comes off the rear of the roof like some of the newer model cars. I find the one i have bangs on my roof when i go over speed bumps and scratches my paint, plus it's ugly! I recently successfully shaved my trunk, but, I was just hoping on a little advice from someone who has maybe done this before, I've seen a couple on here with the antenna shaved.
Basically, I wanted some advice on how to shave the old one, and mount a new one and wire it properly, i can't imagine it would be too difficult, but, i'd rather ask first than just try and screw it up. I tried the search buton and was unable to come up with anything helpful.
Also, i've thus far been unable to find an afterstock antenna that suits my car, any ideas? it would be appreciated

thanks