I’m not sure exactly what you are trying to achieve here. The value in “List/Record” is the type of things that will appear as options in the drop down. What kind of Saved Search is it? That will be the value you put in List/Record. For example, if your saved search is a transaction search, choose “Transaction” from the List/Record. Then, use the filters on the custom field to recreate your search so that the only options that appear in your custom field are the ones you would also get via Saved Search.