So '92-'97 is normal and '97-'05 (possibly further) is abnormal.

As I said, the early MK2 Mondeo box still used a rod change casting (large oil capacity), but presumably the front gearbox/bell housing was changed to delete the mechanical clutch locations and add the hydraulic access.

As the differential didn't change, it seems strange that there was excessive internal clearance or that there was any reason to change the differential part of the casing as the 'normal' clutch is only a pressed steel cover. I would think the clearance problems were more likely to be with the mechanical clutch mechanism and its bearing points.

I run a FRS clutch in a '98 1.8 Mondeo box, which originally had only a 220mm clutch. The casings of the Focus have different transmission bosses to the Mondeo, but the same mechanicals and only slightly different hydraulics. Again, I've had no problem fitting FRS clutch into Focus 2.0 Ghia gearbox.

The Focus RS gearbox has (allegedly) better internals (though bearings are the same) and a Quaife ATB, but the casings are standard '02> Focus MTX75, though a gasket is used between the cases instead of silicon sealant. Perhaps greater distortion under repeated higher torque, though the diesel copes.

I'll admit I've not tried to fit a FRS clutch with a diesel, V6, etc MTX box, but as I've offered before, I'm willing to help any one trying to sort out an uprated clutch in any MTX75 or MT285 if they can supply set-up height as a start.

Martin