You can remove and install a GM antenna from the trunk without removing the OEM trim ring or splicing wires.
I did the same thing for both my antennas. Go to the yard, and get one from a 99. That'* the newest best condition you'll find. Simply drill the rivet heads off of one side of the black gear housing, clean all the old gunk out with q-tips, and re-grease it. Drip oil down the mast, and wipe off the excess. It'll out-last your car. I have one of my old antennas around here that I could do a quick techinfo on, but not until this weekend at the earliest. It'* pretty straightforward. You'll need some screws and nuts to put it back together afterwards.