Here'a couple of pictures. First off, it makes everything so much simpler if the servo is positioned so the cables have a straight shot at the rudder control horns. It's very important the distance between the cables on the horns match the servo arms to prevent binding. I try to ensure that the rudder control horns are installed so that the point where the cable clevises attach (the holes in the horn) are exactly on the rudder hinge centre line. This will ensure no binding occurs as you move the rudder surface. I used pull-pull on the elevator as well in the last 3 fun-fly profile fun-fly planes I've built. If you don't set up pull-pull correctly you can run into problems. Personally I love the "feel" of pull-pull - I think it's much crisper and more direct than nyrods. Hard to beat CF pushrods though for the "direct connection". Here is a link to Brian Felice's web page on Ackerman - you'll find this info very pertinent.
http://members.cox.net/bdfelice/Ackerman/ackerman.htm

Good luck.