77 911 vent fan

[Nanocore]

I have a '77 911 that some time before I purchased it had a non-factory A/C unit installed. Also, prior to my purchase (about 10 years ago) the levers on the dash that affect a fan was not attached. I assume that they were not attached due to the A/C unit installation. I had to replace the engine ('87 3.2) and the condensor wouldn't fit on the deck lid, so I went without and none of the A/C parts went on the new engine. I am now in a position to start adding some of those pieces back in and I am starting with the dash lever for the fan. Now that a lot of pieces were either removed prior to my purchase or not put on when the new engine was put in, I don't know where the fan would be. What is the lever for the fan in the dash is it supposed to be connected to? Will it be visible from under the dash? Is this a true motorized fan or really just a vent flap?