Embrace, extend: https://www.orbiscascade.org/blog/9/?bid=153. Many of the step by steps are directory from the article but may have slight adjustments or notes added.
The solution presumes no ALMA involvement. The outcome is compact full displays with a link out to the record in ArchivesSpace where they can see additional detail and request the item. Several Facets are also enabled to help with surfacing results.
By default an up to date instance of ArchivesSpace will have one on http://yourServerUrl:8082. Since the primo back office will need talk to this endpoint from off campus you will likley have to work with your campus firewall administrator to open this port. There are ways to refine the URL with querystring values to get subsets of data, but the url plus port will allow ingesting all by default.