The two replacement jacks I've installed have four bolts that go through a plate welded to the tongue.
Fairly straightforward. But I have seen some like KState mentioned where the swivel hardware is integrated into the tongue.
Does it look like this? http://www.skidim.com/prodinfo.asp?number=5800496
(on edit)I forgot I had this place bookmarked. You might be able to replace part of the jack if that would be easier.
(Message edited by doug2 on April 24, 2008)