There is a posting on this on OldChevyTrucks. The secret here is that there is a small chamfered area cut out of the body underneath the swaging. This results in a swaged area that is larger that the actual bore. If you bore that out, the ball will press out normally. If I remember correctly, it is about .045" or less. The article to which I am referring talked about using a 20 Ton press with no success, at first.
