Can anyone tell me how to get the outer joint apart on a Ford SuperCoupe halfshaft?

Inner Tri-Lobe was easy but I can't find the key to get the outer joint apart. It is the one that uses the large balls in it to form the joint. 

I can feel the retainer rings on the shaft but can't get to the one on the end to remove the shaft.  I've studied the balls and the cage looking for a particular angle that will allow it to come apart but can't find that either.

Surely there is a way to get the shaft out to change it to a shorter one

Thanks

Paul