you'll need a friend (perhaps your GF that screwed it up in the first place

) to power the radio on and off several times until the motor sucks the base down to the its normal position at the top of the tube.....wow- just realized that sounds a little "inappropriate"
Anyways, another big tip is to compare the teather (flexible plastic with teeth that wrap around the motor) length to the new one. If the old one is much shorter, then part of it could have broken off inside the motor reel - in which case you will need to completely remove the p.ant assemby from the trunk and take the motor reel apart to get out the pieces.
I've done these 100 times...let me know if you have any other questions.
brad