Does the amount of twist in each yoke cable affect the angle of the idler wheel ?

If so ......what is the best way to set it up ? Straight ?

My friend set mine up. He used a straight edge on each side of the pulley. Twist the appropriate yoke cable until you get an equal amount of space on each side from the straight edge to the string. I never read about anyone doing this before and thought this is a great idea. The wheel will now be aligned with the string.

Yes it makes a difference. You need a press to twist the yokes to the certain amount needed so that they make your idler wheel straight.

Thanks guys !! I checked it today and I had it close ..............since I have a set of digital calipers for work........checked it out and was 7 tenths of a mm out on one side.......... loosened the tight side out one twist and now it is only 1 tenth out ! Doesn't get much closer than that !