How to automatically default bargaining unit and union based on collective agreement mapping

Summary: We have a requirement on the Position Details page to default bargaining unit and union based on collective agreement. We already have a mapping in configuration where bargaining unit and union are mapped to specific Collective agreement but they need to be automatically filled in when collective agreement is entered in the position details page. With autocomplete it would become a huge rule with multiple If conditions for around 50 collective agreements. Please help

Content (please ensure you mask any confidential information):Use Case 69 for FORD.

Version (include the version you are using, if applicable):24C

Code Snippet (add any code snippets that support your topic, if applicable):