Not all fields are available in the drop down list when attempting to import F2 Lookup entries from another field
The Field Name entry at the top of the original fields F2Lookup is blank. Once the field name is updated, the lookup import list will show the desired field.
The query GoldMine performs for the F2Lookup list is:
SELECT fieldname, entry FROM dbo.lookup WITH (NOLOCK) WHERE fieldname BETWEEN '0' AND 'ZZZ' AND fieldname LIKE '%H' AND entry > ' ' AND fieldname <> 'MSPUSERNAMH'
Without the Field Name being entered, the entry field for the LOOKUP table is not populated, forcing the field to not show in the import list.