I had to laugh when reading this post, as just yesterday I was in exactly the same predicament. I managed to get the cable off, by losing the handbrake adjustment underneath the car, just in front of the real axle. There are two nylon nuts which when tightened pull the cable tight, Undo these, and enough slack becomes available to slip the top off. It’s still a bit of a fiddle, but none the less, will come off.

Yes, the manual makes it sound so simple, but in reality is not the case.

Good luck.

Cheers
John