It's not hard at all.
Just disconnect it at both ends.
Tie a rope, or fish tape to the steering wheel side. (unless you have the 1 piece rack and pinion. Then attach it to the other side).
Pull the cable out, while pulling the rope through.
Attach the rope to the new cable
Pull it through.
Hook up the ends of the cable.
Grease your rudder as long as your down there.
That's it. You just saved yourself a bunch of money.
Just wondering, is your steering getting tight?
If not, I would wait. They should last 7 years of so. If nothing else. You could order the part and keep it until you really do need it.