OK.....
beating on it resulted in the cage starting to break apart....continued till the cage was broken halfway around, balls fell out, came apart.
You are correct, there is a round circlip like piece, a retainer ring, on the outer part of the shaft, when assembled this was compressed and the star/bearing assembly slid over it, it then springs out slightly to retain the unit.
Damn, though, i broke the cage before i could get it to slide past.....
Now i have to do the drivers side......