Rear Diff help please....

Hi everyone,
I have a leaking rear diff from where the prop meets the diff, so i am guessing this is the Pinion seal....
If it is there are three to choose from, mine is a 1988 90Td and They have the following to choose from, anyone know which i need??
Axle 22S08384B >
> Axle 22S08283B
> Axle 22S08283B

I have no idea which.

Also, i was thinking of renewing the bearings whilst im at it. Now would this be the Pinion inner bearing, or Outer bearing. Or the pair??? are they easy to fit??

any help would be great please.
many thanks
goaty