I was under the impression that ESDI used 3 binary-encoded lines to select up to 8 drives on the same cable, and that there was no way just by swithing them round to have all the drives set to the same number. Certainly the ESDI drive I've just picked up has 3 binary-encoded selection links on the logic board. Of course for the special case of drive 1 and drive 2 (although not drive 0 and drive 1) you can get away with swapping over bits 0 and 1.