With the increase in instances of the manifolds cracking, it makes more financial sense to just replace the manifold instead of the whole turbo.

Remove the Compressor housing by undoing the 4x7mm bolts at the back of the housing. (you could mark their position for reassembly).

Undo the 'v' bracket which holds the turbo unit to the manifold.

Note (and mark if you like) the position of the turbo relative to the manifold. There is a convenient casting mark which points to the centre of the oil feed hole.

Carefully get a thin screwdriver, to just 'break the seal' between the turbo and the manifold.

Do not expect to split the turbo like this, as the fit is very tight. Instead just give it a few taps around this join.

Carefully tap with a hammer the end of the compressor mounting face away from the manifold.

The turbo unit should now come away from the manifold.

Take the opportunity to check the blades for signs of pitting; the turbine wheel should be okay, but pay close attention to the compressor wheel.
Clean up the mounting faces, and clean off some of the soot build up.

Line up the marks again on the new manifold, and push the turbo into place.

Reattach the 'v' bracket, and clamp closed.

Finally, reattach the compressor housing, and tighten until the flange on the turbo is flush with the lip on the compressor housing.

You can identify the correct angle using the marks you made earlier, or by looking at the original bolt positions where it has marked the turbo in the metal.

And you are ready for refit.