Clutch cable keeps breaking

[gtnby2]

I converted my '91 to 5 speed and I keep breaking cables. Has anyone else had this problem? The cables work great for about a week or two and then they slowly get harder and harder to push. I have noticed that when it gets hot out it gets a little easier to push but if the car cools off (and the cable) it gets stiff again. I have had several people try to drive my car to see if the problem was me but they about flip when they try to push in the clutch!!Could it be something to do with the routing of the cable( I looked at factory 5 speeds and did the same) or is it possible I got 4 BAD clutch cables from TWO different sources? I tried taking off the firewall adj. thinking it was binding the cable but it didn't help. The clutch is a Ram HD.....maybe IT is the problem???!!
Any feedback wouldbe great. I have another Question about the Steering rag joint so look it up if you can help with that too.
THANKS,
Brad