I too find it difficult sometimes. Unless you can hold the second end of the line under tension and very still while the CA goes off, it may not stick. Then you find you are trying next time to stick CA on top of CA which doesn't always work either.
With the situation you describe, I would do the same ie glue into the fuselage/tail hole first. At the control horns I usually drill (or use the existing hole cleaned out) through the top end of the horn (side to side) and loop the line through and gently tension by pulling back in the original direction. Seal the "loose" end to the tensioned line with a tiny drop of CA (or even tie in a knot if flexible enough) and cut off the spare. Occasionally I end up cutting off the rigged line too
If the model has a turnbuckle at the horn end of the line, I either fix the buckle on the horn first or do a simple representation by slipping a length of brass tube on the line. Check reference pics because some rigging doesn't have turnbuckles (just ferrules to close the eyelets) or rigging may even pass through the horn front to back, in which case I would try and cut a slot along the top of the horn into which the line can sit.
I use EZ line mostly, or the elastic you can get from WNW, as this is very flexible and forgiving!
