i will defo be looking at the second option tomoz thanks
You can take off BOTH turbo end casings without a worry.
Just take care not to bash the turbine blades about.
The ONLY moving part is the shaft with the two rotor blades on it, and if handled reasonably it will be fine.
Taking out the bolts that secure the turbo body to the exhaust turbine casing might not be so easy.
HOWEVER .... you can test for this problem without stripping it at all.
Have a look at the waste gate lever while the engine is stopped.
The lever is in GATE CLOSED position.
Take off the operating rod, then move the lever fully the other way (waste gate wide open) and secure it like that with a bit of wire.
Go for a drive.
If there is no boost that is because the gate is open and it works.
The fault is probably not in the turbo.
If there is full boost even with the LEVER in "gate open" position, this means the gate disc or flap MUST be jammed CLOSED, preventing by-pass flow and causing over-boosting.
So easy to do so it would be my first check.
CharlesY