Network-Managed Records in a Network Zone When working at a member institution in a collaborative network, you can manage bibliographic and authority records at either the institution or network level.

above-linked ex libris documentation focuses on using local extensions with CZ records, but you can do the same thing with NZ records. ex libris covers this here: knowledge.exlibrisgroup.com/Alma/Product...

sorry, i misspoke: we would use local extension fields with shared *NZ* records (not CZ records)

Working with Local Extension Fields for Community Zone-linked Records

would using local extension fields be an option for you? at my prev institution, we would use these in cases where we wanted to add local field content to a shared CZ record. such fields are not visible outside the local institution. see: knowledge.exlibrisgroup.com/Alma/Product...