I am more than certain the air guide on my 82SC has the cut out for the voltage regulator 180 degrees opposite the one in the above photo, as the metal vanes on mine were slightly loose so I drilled out the rivets and replaced them to tighten things up. The upper vane wasn't hanging in the breeze as above, and the voltage regulator was oriented on the bottom of the assembly.
Here is a link to the Porsche TSB:
http://bethnrayndogs.com/car_docs/Porsche/porsche/Porsche_Tech/Porsche_TECHNICAL_BOOKS/Tech_Bulletins/Group27_82-02.pdf