Hello,
If the antenna is stuck it could be it has a kink in it. I just replaced my antenna and you have to unscrew it from the outside. Look for two small holes in cap that the antenna goes down into. The holes are for a tool that unscrews that cap. The antenna will fall over and then power up the antenna and it should unroll the nylon thread coil and come out. Install the new one the same way. Be very carefull not to kink the new one. They cost about $50.00..ken