Oracle Premiere - what's the difference

I have been trying to determine the difference between the Oracle Premiere and Oracle Delphi for various Mark versions. I havent really been able to get a definitive answer from Jacques at Oracle. For instance, the Premiere Mk II has the same suspension towers as the Delphi Mk III, but does it have the same motor? The Delphi MkIII has an AC motor. The Mk II has a 24vdc motor. The Mk II Premiere has an outboard power supply with digital readout of speed. How is that different than the Turbo power supply? The Mk II Premiere has an adjustment on the side of the bearing housing that is not on the Delphi either MK II or III. Is it a different bearing? I know the subchassis on the Premiere is larger, but is that the only difference? Surely someone here must know, or be able to point me in the right direction.
The reason I am asking, is that I like the Premiere's larger frame, but dont know how the other parts changed over the various Mk versions compared to the delphi. For instance, I have read that the MK IV Delphi used the bearing from the Premiere. The MK IV bearing had the nylon adjustments. Is that the adjustment screw I see on the Mk II Premiere?
thanks for any help