That panel pops off fairly easy. You can pry just that panel off or pull the whole larger panel off ( the one holding the a/c controls and the radio) the radio will not come out with the panel. Just open the ash tray and pull on the bottom corners of the larger panel and then pull the upper part of the panel straight out. Once the panel is off don't pull it out to far, you will need to disconnect the airbag warning light at the top of the panel and disconnect the a/c controls. This way you can then see where the wires go to from the switch you are asking about.

 

since i cant figure out how to post the pic on with the reply i put it on my albums...

 

Looked at the pic. That is definitly an aftermarket switch. As in my last post I would pull the panel and trace the wires to see where they go.