Hi, I gave a 930 77 Tranny and recently ordered the cable from our host (PP), part number:
930-423-401-05-M74
It had the rubber booty and hook end already on it. Below is a photo of it installed. I couldn't get my helper spring setup correctly, so I don't use that part of the clutch setup anymore. Seems to work just fine without it.
I hope that helps, Mike