No luck with the SASI/SCSI yet, I will experiment with latching the select and see how I get on.
As an aside, I found a Teac 55F in a pile of rubbish some guy was clearing out. I cleaned it up attached it as B: and knocked up some code to copy the system track from A: (Gotek) to B:. I swapped the drives over and I am now booting to the floppy with the Gotek as B: It suddenly seems far more vintage.
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