96 Sentra: Need help on replacing cv joint boot

My 96 Sentra GXE has a torn CV joint boot on the drivers side. It is
the outer boot and it appears to have occurred recently. I want to
replace the boot, but it entails the somewhat difficult job of getting
the outer cv joint off. I have had bad luck in getting the cv joint
off the drive shaft in the past, and I would like some suggestions.
I can take the drive shaft off easily enough. My problem is when I
try to get the joint off, invariably the cage and ball bearing come
falling out. And.... it is a real problem getting them back in. I
would like to know of any trick to get the cv joint off, without
everything coming apart.

Al