Pat.
I had the same trouble with the parking brake cable on my 46 one ton. Cables were rusted solid at front attachment point. New cables were not available.
Here's my solution. Remove brake cable from housing.
On a bench grinder, carefully grind away 1-2" of the cable sheathing on the 'front end' of the cable. Work slowly and carefully, rotating the cable to remove the metal housing evenly. When all sheathing is removed, soak cable in penetrating oil overnight.
Next morning, lock brake end in vise and work cable loose with vise grips. When free, coat
in grease. Attach a length of 1/8" aircraft cable with crimp clamps. Use 2 clamps. Crimp in vise.
Reinstall, attaching aircraft cable to parking brake linkage. Use crimp clamp, or 'u-type'clamps to secure. Adjust linkage as necessary. Remember to re-grease the 'open end' of the cable when you grease the truck.
My fix has lasted for two years and counting.
Good luck.
