I won't buy a clutch cable from anywhere but maximum motorsports. Almost everywhere that you can pick up a cable makes them different than the way the original factory ones were. I went through about 5 cables until I got pissed and ordered one online. I haven't had any troubles with this one.
http://www.maximummotorsports.com/
Here's what they say about it.
"We have done a lot of research on clutch cables, buying and testing almost every different cable on the market we could find. We have found after all this investigation, that the OEM Ford Clutch Cables are the best quality cables available. They have a multi-material, layered construction that provides better heat, friction and collapsibility protection than all the aftermarket cables we dissected. With that in mind, we have begun selling all year ranges of factory cables, for those customers that demand a cable that will last.
We have developed a clutch adjustment package that will work with all OEM Ford cables. Our Quadrant, firewall package will allow the use of all OEM Ford cables (and adjustable cables, too), however the cables all require some minor modifications. We also sell a package with the MM Universal Ford OEM cable, which comes with all the parts you need to install a Ford quality cable with an aluminum quadrant and firewall adjuster, that requires no additional cable modifications. This universal cable will provide more header clearance, and therefore even better heat protection, than any other cable we have found, including the 5.0 liter engine OEM Ford cables!! This cable, quadrant and firewall adjuster can be the answer to all your clutch cable problems! We have also discontinued selling adjustable clutch cables due to the poor quality and repeated returns we have experienced. Based on our research and ongoing testing, OEM Ford cables are the only solution to clutch cable problems."