How is it possible to install parking lock cable on a 65 904?

I finally tackled the parking lock cable leak on my 1965 Valiant 170/Column Shift 904. Apparently the reason why the factory procedure didn't work for removing the cable was because there was nothing ever hooked up inside the parking lock cover. I had to remove the cover to see how to get the cable off but when I got the cover off it wasn't even connected to the little adapter. Probably the reason for leaking. Now I've got it cleaned, put a new oring on the cable, and new parking cover gasket. However, I don't see how it's even possible to hook this cable back up. There's no way the factory procedure will work. I played with it with the cover off to see everything works. I see the tangs on the adapter go between the parking pawl hook and the end of the spring wraps around it. If I install the adapter on and try in install the cable I can get it hooked but the adapter lock spring has to be moved over in the lock position. I finally think I got it but that's not good. What if the spring is the only thing connected to the parking pawl? It could work a few times and then down the hill it goes. It looks like a very dangerous design. If you don't have that thing 100% hooked up right your car is going down the hill. Has anyone come up with a 100% sure way to get it connected? I doubt any of the shops in my area could do it either.