In Management>Import, select the MARC Radio button.
From then on, see the attached screenshot for the settings
Selecting “MARC-21 Authority’ in the ‘MARC format’ field is crucial.
It is important to select ‘Load subjects’ otherwise the subject authorities won’t be loaded (which is really the point of having a subject authority).
As for the ‘Existing Records’ options. For authorities we want to replace what was there with the new SCIS authorities, so we select “Replace existing resources”.
The last time we loaded the reference only file (RSAF-marc.dat) it took 2.5 hours to process we therefore recommend that this is an overnight housekeeping task