Spotted this on the web, it is a video guide produced by Garret ... it may have been posted before but worth doing again I think.
Garrett by Honeywell Turbo Replacement on DV6TED4 Engine
Hopefully nobody will ever need to use it
Okay but the oil filter should be removed before the oil is drained and sump removed, they have just drained the dirty oil out of the filter into the sump!
The oil pump only needs replacing if the engine is big time carboned up due to leaking injectors.
The vacuum pump has a filter in it that needs cleaning out.
The turbo feed pipe does not need replacing you can clean and modify it. you can also modify the oil strainer.
Good point polar filter off first then drain the sump then sump off then take the oil feed pipe off take a good look at the strainer to see if it's clean if it is take the strainer off and us the pipe with out it you can buy a new one from Citroen with out the strainer around £15 if there's a lot of sludge in the sump it will need a good clean the oil pick up pipe with strainer in the sump will need replacing if it's all clean then there's no need to replace it .