There is really no need to take the (CHRA)Centre housing rotating asembly apart.
If the turbo is past it's use by date you simply get a xchange CHRA.
Unfortunetly u need special tools to go any further than u have.
But if u want to learn and the turbo is of no value to u u coud just take the wheels off with
any suitable tool (What r u finding difficult to do)
If u wan't to use your turbo again i would get the suitable tools and also mark the position of the wheels in assotiation to the shaft (As they r balanced after assembly)moving them even a fraction will cause most likely a early turbo failure)
Well i had plans on putting a turbo on my mi16 (I wouldnt have done it myself though )
The turbo is of no value for me, i bought it for 500kr = 89 aus.$ I mainly want to take apart to learn
I can seem to pull the shaft of the turbine blade and i dont want to use alot of force either... Well it is old so that explains why everthing is hard to dismantle hehe