From my modeling experience you can have the distance narrower at the servo end then at the rudder end. But not in reverse as the lines will get too much slack when pulled to one direction or the other. the difference can't be too great either as binding will occur. I've used pull - pull on my airplanes and have always tried to keep the distance the same. If it meant that I had to move the lines in closer in on the rudder control horn then that's what I did. Do a search on this site for pull - pull control type installations and you'll get a lot of info.

Cheers