There is 100% a little rubber bizzo that wedges in between where the cable end goes into the pedal. This stops the cable un-hooking if you pull the pedal back up towards the dash. Will try and get a pic but it is really hard to see it. I don't have a parts book, but surely someone has a WB one out there with a picture of the clutch pedal assembly. Mine is an April 84 one, so maybe it is a late update as well.
As long as it passes the brake test you will be good to go. Also make sure you have some idea if the place doing your blue slip has any compassion towards old cars or they can make getting a old series car hard to get through. Stupid stuff like sagged door hinges etc become a top priority to some power tripper paper pushers.
Bookmarks