320mm rotors and calipers from S40/V50T5 AWD & LS-LV Focus ST are a great improvement over the 280 and 302mm 850 and x70 brakes.
The calipers are inexpensive and there isnt much to do to get them fitted.

Here's the 320mm rotor vs the 280mm -

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Rotor fitted (requires centrebore to be enlarged to 68mm) -

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Caliper fitted -

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Test fitting with the adaptor (before coating). Please ignore mismatched fasteners. -

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Wheel clearance with a Titan -

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