Here's a tail shot showing how I have the cables running. The upper elev cables run through an eyelet on the leading edge of the stab. The full-size has a short bar that runs through the eyelet with the cables attached to each end of it.

I used braided nylon fishing line for the rudder cables because I didn't want to have parallel metal wires (possible RF noise). They have held up just fine on a 1/4 scale plane. I used the cable that Balsa USA sells for the elevators. If yours is a smaller plane the fishing line should be OK for everything.

Jim