Just saw this and am contemplating getting one to set back for my x320 one day but I have a few questions hoping somebody can help me with. First, will this even work with a x320? Will I need the upgrade kit or is that just for tractors with the 1/2" axles? He says his upgrade kits are around $400 if I recall correctly and I really don't have that little confidence in the K58 to spend that kind of money on upgrading? Second, I know TT still makes these, so is there an abundance of these out there at this price? Thanks.