I'm not sure about the newer two variants of the 99 but the I think the oldest variant without the add on block would just look similar to 98.
Here the designer himself is posing in front of what is probably the original 99 (some term it 98)
The 98 and the original 99 had this distinctive circular hump on the top of the turret which was absent in the subsequent variant seen at the 09' parade and the newest boxy version. I am not sure what the newer version without the hump on top would look like when you remove the add on blocks.
The designer studied the soviet T-72 before settling on a design of the 99, so won't be surprised if the earliest variant at least shares some similarities with the T-72: