rr 4.4 03 plate need advice

had a nightmare of a job ball joint. but job done now but unfortunatly the inner cv joint has came out on inspection there was a lot of play in the shaft and looked if it wasnt long enough to fit properly on the inner joint so stripped it all down again and took of the shaft. now here is the tricky bit how does it go back together i have noticed that inside the shaft there is a clip at the top of the shaft (inner) and also a ring shaped like a 50p with ball bearings in it that if you touch it it slides up and down the inside of the drive shaft. i take it i need to put this onto the cv joint shaft (inner) but it is puzzling cause if you try to put it on the shaft it just retracts back down the shaft.

heeeeeelp