When an item has multiple separate LHRs, they may not display in the order you want in Discovery. To change this without changing the information in the displaying fields of the LHR, add a copy number (852 $t) to each LHR. 852 $t 1 will display on the top, 852 $t 2 beneath that, and so on. The copy number does not display in Discovery, so you will not need to edit the call number or any other Local Holding Record field.
Please review our Bibliographic Formats and Standards for more information on the 852 field.