ask the seller for the Serial number for the table. It is located on the left front leg (under controller) on the later models. You can then get hold of PlasmaCAM direct and they will be able to tell you which model it is. The DHC and DHC2 are the better to go for. I don't believe you can update the older 98Z with out virtually buying a whole new table. If possible you may also be able to see which type of torch holder it has. The older models had a single clamp system on the handle where as the DHC2 has a twin clamp system holding the handle and head.