I have a 1979 928 in great condition. The headlights worked great until today. I was changing the bulbs and had the shrouds pulled back but not off and I went to test them and they retracted sending the shrouds down behind them in the fender. I got them out and installed but now the headlights don't go up and down to the correct positions. They do manually by turning the motor over ride knob. Are there limit switches that I bumped? Where?