I had same problem in my '95. Only way to fix it is to replace the entire assembly. You need to remove the interior trim around the door from the dashboard all the way back and including the side panel behind the door. The assembly includes the guide track above and behind the door and extends to the motor and winding spool bolted to the frame near the floor. The assembly is not repairable. The cable has a Teflon casing to stiffen it so it can push as well as pull the emergency release catch along the guide rail. Over time the casing cracks and splits and the cable inside slips out instead of pushing the catch. As far as I can determine the part is only available from Ford, and is not inexpensive. You might possibly be able to retrofit a 3-point retractable lap/shoulder belt but I don't know if there is a place to mount the guide at the top. I'm sure you can tap a hole in the frame to bolt it in, but this may not be legal - I have no idea how well this would hold in an accident. I'm not an engineer.
Allan
May 2007
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