The problem with the blue m3 brake calipers (the stock ones) and the 435 style calipers (both M brake calipers and stock calipers) is that the mounting lugs are fixed.
So radial and axial offset is very difficult to alter. That means that only a certain disc with a certain offset and certain diameter is going to work.
Only the 6 piston M3/4 carbon brake calipers have a bracket, for which you could mill a new, custom one. That way you have control over what radial/axial offset you want to use for your planned rotor.
But those calipers are gold, not blue
That type of bracket that is used on the 6 piston carbon brake calipers is similar (not the same) as for instance is used on the 135i 6 piston brembo calipers. For those last calipers there are multiple aftermarket bracket manufacturers to fit them on say a z4 or z4m.
Then again if you're buying new rotors, new calipers and new brackets, something like a D2 racing BBK is just as expensive.
Fitting rear calipers gives even more complications
Took me about 2 weeks to fabricate a custom rear brembo caliper/rotor brake setup in the evenings and weekends....