The clutch cable attaches to the bottom passenger side of the bell housing with an adjuster nut and a lock nut. Use two pair of pliers, one to hold the adjuster nut and the other to loosten the lock nut. Remove  both of these and slide cable out of the arm. Once the cable is loose it will be easy to follow up to the fire wall where it is attached by two bolts. Remove the two bolts. Then reach inside the truck and remove the 'hook' on the cable end and completely remove the cable from the truck. You should be able to hold the cable housing and freely move the cable inside the housing, if not clean and lube it good and see if it frees it up, or just get you another one. If you reverse the process above you can easily re-install the cable.
Pay attention to the position that the adjuster holds the arm on the side of the bell housing when you remove it and when re-installing it just adjust the nut to hold the are at about the same location.
Zig