friend of mine rebuilt his own turbo, the trick was to mark up the turbines and shaft so that they went back on in exactly the same place so as not to be out of balance when re-assembling, worked ok for a year or so then he sold the car, if the shaft is knackered then you may run into trouble with balacing the unit, the bearing is a floating unit where the turbine relies on oil pressure and balance to run true and so that the turbines dont hit their casings when moving, i've never been brave enough to rebuild my own always gone down the recon or s/h unit approach, good luck and let us know how you get on