Everytime I use my emergancy brake after I release it, the brakes drag.

I've replaced the brakes a few months ago cause they were wore out so weak springs can be ruled out.
I'm leaning towards the cables sticking. How difficult is it to repalce them? Can they be done in an afternoon. Will I be able to figure it out once I get under there or will I need a repair book?

 

Doing mine this weekend. There are three parts, the front that leads to the pedal, the intermediate that controls the left drum and connects the right drum cable, then the right drum cable. My right drum cable was beyond stuck, I could not pull the cable for anything. That was the cause of my drag though any of those three could cause it.
It's no harder than doing the brakes, but it is easier if you have them apart alreadt as I did. It is tedious though, and a pain fighting to get enough slack to do it.