Look in the same link
Good homework, if you read towards the end, you will see it was succesfully installed and calibrated. There is another post from sbourg that explains the same thing. It has the link to the online parts store. I wonder if Bill at parts shop will start selling the potentiometer by itself.
1999 Porsche 996 Carrera Convertible
1994 420E - SOLD
1986 300E - SOLD, what a car