Update here, turned into a bit of a bugger of a job had to call in a mechanic / mate to assist. We just couldn’t get the leverage with those exhaust nuts through the wheel arch, they were so badly seized. In the end we removed IRD to get better access. I’m fairly certain we found the culprit, I couldn’t believe it but the return oil pipe didn’t even have any bolts connecting it to the turbo, the gasket was just wobbling around in between the telephone pipe, I’m not sure if they had vibrated out perhaps!
Now the oil has actually made stains above the Turbo On the back of the engine block, I’ve taken a picture, my assessment is that the oil could have sprayed up from the return pipe whilst driving with wind etc, what are you thoughts? Rather than some other seal on the engine above the turbo?
Anyway thanks for your help so far as knowing which bits to remove in the turbo itself was invaluable once we had the IRD off, I have the new gaskets etc, just need to get bolts etc and a few other parts which were killed in action during the removal. The turbo seems in good condition no movement on turbine.