Has anyone replaced the top activation switch that is mounted on the top frame right next to the passengers head? Sometimes mine works and sometimes it doesn't. It appears to be mounted by two screws into the top frame. I also can't see what pushes the switch up and down. The new one also has a hole for another bolt and an electrical connection. I can't see where these are on the top frame. Can anyone give me directions or photos or something before I start taking it apart? Any info would be appreciated.i