403 - "A" frame attachment to differential on back axle

[mikebro]

I've got the ("A" frame) Attachment off the car to fit new rubbers to the swivels, and a new oil seal to the ball joint. The swivel rubbers are no problem. My question concerns the oil seal for the ball joint at the rear of the attachment. Is it possible to fit the new seal without splitting the ball joint? Is it possible to split the ball joint without removing the diff from the back axle, which also involves removing the half shafts? If I really do have to take the diff out, it would be good to know of any tips, pitfalls etc. - I have a copy of the service manual, but some first hand knowledge would be much appreciated.