It sure is possible! I did one on my old mans VS Acclaim! I brought one of the Aerpro fully automatic antennas from JB Hi-Fi for $99 n installed it myself!
The front left wheel has got to come off and the car has to be jacked up! If you have mudflaps, they have to be removed first, then you will find about 4 screw clips, remove those and then carefully remove the splash panel and it will reveal the original antenna!, just unscrew that, but leave the mounting bracket there!
With the antenna you get, you should have some mounting brackets. attatch these to the antenna, along with the bracket that already came off the original and then whack her in, making sure shes nice and secure! you will see a hole for a grommet! whack all the wires inside it!
now working from the inside of the car, u have to remove the glovebox and the black plastic panel that lies underneath! once thats done, get someone else to hold a torch while u fish up there with your hands trying to grab the cables u stuffed through! once u have them, then run the antenna wire to around the left kick panel (theres an adapter there, look for the old one) and then run the other 2 wires up 2 the headunit (should be red and green), then wire the red one into the positive +12v of the headunit (this way the antenna can decend without the ignition being turned on incase u forget to turn it off before u turn the car off) and then the green wire to the remote antenna wire of the headunit (usually blue)
then all going well, it should work first time!
hope this helps!