No issues with wires rubbing. Been a year on my wires and no issues... speaking of which, time to freshen up my wires.
Run the wires forward so its easier to pull or adjust the slipper.
http://www.rctech.net/forum/11886147-post3292.html

Diff just seems to want to be that tight to be right. Make a cool tool for easy adjustments.

I run a 19t / stock spur with a 6.5 so you will want a little bigger pinion.