Whilst greasing up the starter solonoid, which involved taking the egg-sauce downpipe offed, I stuck my finger in the turbo and felt something move - which I thought seemed wrong.
Turns out this:
Was missing from here:
Meaning the actuator linkage wan't attached to the turbo. That'll explain the total lack of power and view in the rear view mirror ('cos the road was obliterated wiv black smoke!)
Once I get the bits off I want for Itchy, Scratchy will be for sale with MOT until September (IIRC).