tomlee59 has succinctly summed up the possibilities, and it were de trop to paint his lily except to record that the Classic II's PDS slot is different again from other AIO compact PDS slots, and there was never anything made for it but a 68882 (FPU) card, which is rare.

If you have a suitable disk utility (program) it is possible to account during setup for the slow SCSI of Plus and SE, which have 'interleave ratios' of 3:1 and 2:1 respectively, that is, how many platter revolutions are needed to read a complete track.

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