'67 c10 4l60 swap, e-brake question.

[LH Lead-Foot]

For the rear E-Brake cable that comes wrapped in wire, I lube these off vehicle with motor oil then put some convoluted wire cover over it, with the split facing down to let any water drain out.
I have had a number for frozen rear cable over the years and replacement came in the exact same fashion.
As a motorcycle guy, on Yamaha #17 (102 Cu In, bags & windshield / first one, a 90cc step-thru with side mount carb with disc for crankcase intake timing in 1969), I had two cans of cable lube with hose & attachment. If it fits and you practice a little, it works great. But it won't fit the large cables on the E-Brake system. Most with automatics never use them but should.
I see the rear cables shown in the photos by TA_C10, are complete PVC covering. Now thats the way to go. Once again, the covered from cable should keep them looking good for years. After all, we want to spend more time in it, than under it.