I have gone through 2 different sunroof motors on 98 CSVT and the third one is working so far. the problem is heat! i live in sunny Florida and i made the mistake TWICE, by trying to open the sunroof while the car was extremely hot (sitting in the sun). These plastic gears strip very easily, which they are supposed to do in order to protect the motor. the key is to open the sunroof when the temp is moderately cool. i know this sucks because you want to open the dang thing when it is hot. so anyway, its like the plastic impellar water pump situation. who in their right mind would specify a plastic impellar in a water pump? Welcome to the lovely world of Ford.
Michigan climate is relatively cool...
Marty