Missing thrust balls and washers?
 

Am i being stupid or do the thrust balls and washers somehow get embedded into the diff (b44) or should they be obvious when i take the biff apart?

At the mo it looks like i have neither balls or washers?

I have found that they do stick in the outdrive because of the black grease used. Just stick a driver in and flick them out.

Ive reckoned to do that but will have a proper poke about. The bores seem clear and smooth though.

The reason i was stripping down was to see why my diff was coming loose all the time. Would lack of balls etc cause this?

Yes, definatly. It is the thrust race that let's the screw turn independently of the outdrive that houses it. Try sticking the driver through the other side of the outdrive this usually works quite well it there is anything in there.