I used a variation of the socket method. Not having a 1/2" extension long enough to do the trick, I used all threaded rod to pull it in. Doesn't control the seal very well, I don't plan to try it again.
I have two XJs, the 99 had the seals replaced by a pro using the socket and hammer method twice, leaked both times. I'm taking it back this week for a third pair.
If it still leaks, I'll do it myself. In the mean time I have a 96 that had a seal replacement using the all thread rod and socket. The leak is so minor that it hardly wets the lower ball joint. If I have to do the 99, I'll do a production run and do both at the same time plus a U joint change in one of them.
I don't like the "pull the socket" or "hammer the socket" methods.
I'll have to buy a tool. The FSM tool was my first choise but at $100, it is a bit high. The tool mentioned earlier is half that.