I am in the process of setting up my c-band dish (7ft unimesh) and have a question about this lnbf. When setting the f/d ratio which surface do you go by to line up with the scale on the side? I assumed you go by the back edge where the set screw is. When setting the focal length do you go 1/4" inside of the feedhorn or do you go to the flat surface of the inner most ring, or on top of the inner most ring? I have also read that some of the C2 lnbfs should be set to 9 or 3 o' clock because it is 90deg. off. That is fine but how do I know if MY particular one is off or made correctly? When set "properly" which direction should the "bar" that runs from side to side be facing?