Not only that, the turbine wheel is not a T28 turbine wheel. The T28 turbine "upgrade" wheel is only 10 fins, whereas the stock T25 wheel is 11 fins, and they are thinner.
That is a bone stock T25 unit. No one would rebuild a turbo and have it look as dirty as it was received. See my turbo rebuild How-To. If you don't clean up the turbo, you may as well not have touched it at all.