LCGuy, I wouldn't worry too much. Actually I think there's a good case to be made that it would work if the Apple 5.25 uses the same 20 pin drive header connector. Fortunately on the DB-19 connectors, Apple standardized the pinouts pretty closely between platforms. All the voltages match properly, so there's no chance of frying anything by a voltage going into a circuit path not intended for one. The UniDisk & 3.5 have interface boards, but I don't know about the FDHD/Superdrive, I would assume that to be the case if it still supports passthrough, but perhaps that circuity's not necessary with a single drive?