I just installed a SCSI2SD V6 in my EIII rack.
Here's some tricks that can be useful.
The EIII had an internal 1 GB SCSI CF converter installed on SCSI 1 (boot HD)
1. I put the EIII on SCSI 0
2. Removed the floppy drive
3. Put 6 SCSI partitions on the SCSI2SD, 1 GB each, on a 8 GB SDHC card. After the 10 seconds formatting process, switched of the EIII (don't need to wait for the verify process on removable drives)
4. Copied the OS in each SCSI drive
5. Installed the SCSI2SD in the floppy bay with a 3D printed case
https://durhamcardco.com/scsi2sd-v6-internal-case-preorder-.html. I asked for a 3 cm high special printed case since the EIII floppy is higher than the standard floppy size (2,5 cm).
6. Connected both CF card converter and SCSI2SD
The EIII now works on 7 SCSI partitions of 1 GB : SCSI 1 (CF) and SCSI 2-3-4-5-6-7 (SCSI2SD)
It seems that removing the floppy drive lets you put the EIII on SCSI 0. Don't know why...
The SD cards in SCSI2SD are of course hot swappable...
I tried to format 7 SCSI partitions on SCSI2SD (1 to 7) and remove the existing CF converter but this did not work (the EIII checks the SCSI bus over and over and never boots...).
Hope this helps...