I changed my stock antenna for a power antenna but the harness coming off of it seems not to have anything to plug into. It has three wires, a white a green and a gray. When applying ground to the white and power to the green, the antenna extends. Problem is, when these are reversed is the only way to get the antenna to retract. My radio did come with the accesory wire that is usually used for power antennas or to power accesories only when the radio is on. However I don't know to which wire it should go. Finally, I remember having once a setup where the power antenna was only up if the source for the stereo was the radio, once I switched to cd or tape, the antenna went down. Is there a way to do this with this antenna?