Bootcamp - internal error (ex- fusion drive)

Hi

I have an iMac 17,1. I've made a hardware change: upgrading the HDD to a SSD. This means I now have a fairly useless and spare ssd connected which used to be part of the fusion drive (24gb), there is nothing stored here and it has been formatted. The OS and everything is installed on my 500gb SSD

When I open BC I get 'Internal Error' when I click continue. Looking at previous questions I suspect I have an unsupported setup.

Is there anything I can do to get my setup back into a position where BC will be happy, without having to delete and reinstall OSX and all my data? Bearing in mind I would disable the spare 24gb ssd if I could, I don't need it.

Thanks for your help!

/dev/disk0 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *24.0 GB    disk0
   1:                        EFI EFI                     314.6 MB   disk0s1
   2:                  Apple_HFS Spare SSD               23.6 GB    disk0s2


/dev/disk1 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *480.1 GB   disk1
   1:                        EFI EFI                     209.7 MB   disk1s1
   2:                 Apple_APFS Container disk2         479.9 GB   disk1s2


/dev/disk2 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +479.9 GB   disk2
                                 Physical Store disk1s2
   1:                APFS Volume SSD - Data              360.0 GB   disk2s1
   2:                APFS Volume Preboot                 84.0 MB    disk2s2
   3:                APFS Volume Recovery                528.5 MB   disk2s3
   4:                APFS Volume VM                      4.3 GB     disk2s4
   5:                APFS Volume SSD                     11.2 GB    disk2s5