I need to replace my antenna and have read the links... One mentions removing a bolt and pulling the liner down to get at the motor.. I have checked and can only see that the liner is held in place by multiple plastic fasteners.. I think the center pin pops out and the fastener will come out.. Is this correct or am I going about it all wrong? I tried to pop the plastic center pin out of one of the fasteners and only accomplished popping off the head of the plastic fastener.. What am I doing wrong? Thank you if you can enlighten me..