If that is the case, the '86-'90 procedure in the book is wrong, or so it would seem. There's a hole for a roll pin, or so it looks like to me, on the hydraulic line coupling:



If that is the case, then you should be able to put the line in and put a new roll pin in and be good to go. I'd like to figure out the dimensions of that (both) ends of the hydraulic line so I could make a fitting that could stay in place permanently and convert it over to AN connectors so I could just run a flex hose or something. I really don't like how these are set up, I like the external slave setup better.