the mast can be replaced separately without removing the motor from the car. To do it, you need to remove the upper collar and nut from the antenna assembly, then turn the radio "on" to raise the antenna mast. You won't be able to get the antenna mast out of the unit unless you have the motor connected to the electrical system. if the antenna is broken, then turn the radio 'on' and gently pull up on whatever is left of the mast until you get to the mast nut. The mast nut is a long, tubular, multi-sided nut that surrounds the mast at the bottom of the mast assembly. Use an open end wrench to unscrew the nut and then you can pull the mast and drive tape out. you can then replace the mast with the Honda replacement mast (putting the drive tape through the special mast nut first), tighten the mast nut, reinstall the collar assembly to the motor housing and you should be good to go.if that sounds too complicated, send me your email and I can send a pdf to you (I can't attach a pdf to an Yahoo answer)hope that helps