I purchased a brand new cast iron manifold from an Ebay seller and have given it to the garage for fitting. They are also changing the breather filter / housing on the top of the engine. I think the engine is ok and was told the cats may have survived but they are sealed so no way of actually clearing any excess oil. The turbo according to them was part exchanged to keep the cost down and would have cost another £400 if not with BMW.
Also mentioned were pre-heaters which smelt a bit??!! The car has 94k on the clock by the way and had a full service including fuel filter etc and BMW about 18 months ago.
When I get the final bill I'll post here again! It was due an oil service but I guess after this I can say its had an oil change and all sorts carried out.

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2004 BMW X5 3.0D
1985 Porsche Turbo 930
2000 BMW 328i
1985 RS Turbo Series 1 (Concours)
1984 Escort XR3i