Forget about the nut part, was thinking about a different setup. Technically every time you rebuild a turbo, you should get it rebalanced. The compressor wheel is torqued on, then it is spun, cut etc... When you take it back off and put it back on, when tightened up it will not be in the exact same place. This makes it slightly out of balance.
Derail over
Its okay if it has some side to side. The in and out play is what you need to be worried about. These journal bearing turbos aren't the tightest setup, and without being held up with oil it'll have side to side play.