I have a replacement antenna and am trying to get the bolt screwed off toget the old antenna off, but it's stuck, doesn't move. I've tried a needle nose plyer like described on other sites and even a vice grip. I have tried to spray some lubricant in to loosen it, but no difference. My next guess is that the mount underneath it needs to be broken off to get at it. Any new ideas (outside of going to a shop) would be appreciated!

 

I have 97 Montero Sport, the antenna will not go up anymore and can hear grinding noise. I jack up the SUV, remove passenger side front tire,. Remove wheel/tire shroud if you can. I only removed screws on the back side, disconnected power supply to the motor, removed 2 motor mounting screws. Found broken plastic gear. I did not have replacement motor and I just re-mounted it. I just manually raise or lower the antenna.