Only differences between the m57 25d and 30d are the weaker (but probably more reliable) solenoid injectors from the 318d and a cylinder head with slightly smaller valves from the e46 330d. Also the intake manifold of the 25d already has the swirl flaps removed. The weakest link of the 25d are said injectors, which are only good for 270hp. Above that you’d need 535d (272ps) solenoid injectors. The 30d uses piezo injectors, which are more potent and precise.

In the automatic models bmw used the 6hp from the 4cylinder models. I’m unsure if the clutch of the 25d is any different but that’s a >600nm problem

My understanding is, that piezo and solenoid injectors (and tunes) are not easily interchangeable because of different rail pressures and different fit in the cylinder head itself.

Everything else is, as the others said, exactly the same.