diff --git a/iaso/models/data_source.py b/iaso/models/data_source.py
index 7dee0e81de..fa9c0153fa 100644
--- a/iaso/models/data_source.py
+++ b/iaso/models/data_source.py
@@ -262,15 +262,15 @@ def clean_data_source_versions(self) -> None:
     def create_json_diff(
         self,
         logger_to_use: logging.Logger = None,
-        source_version_to_update_validation_status: typing.Union[str, None] = None,
-        source_version_to_update_top_org_unit: typing.Union[int, "OrgUnit", None] = None,
-        source_version_to_update_org_unit_types: typing.Optional[list["OrgUnitType"]] = None,
-        source_version_to_compare_with_validation_status: typing.Union[str, None] = None,
-        source_version_to_compare_with_top_org_unit: typing.Union[int, "OrgUnit", None] = None,
-        source_version_to_compare_with_org_unit_types: typing.Optional[list["OrgUnitType"]] = None,
-        ignore_groups: typing.Optional[bool] = False,
-        show_deleted_org_units: typing.Optional[bool] = False,
-        field_names: typing.Optional[list[str]] = None,
+        source_version_to_update_validation_status: str = None,
+        source_version_to_update_top_org_unit: "OrgUnit" = None,
+        source_version_to_update_org_unit_types: list["OrgUnitType"] = None,
+        source_version_to_compare_with_validation_status: str = None,
+        source_version_to_compare_with_top_org_unit: "OrgUnit" = None,
+        source_version_to_compare_with_org_unit_types: list["OrgUnitType"] = None,
+        ignore_groups: bool = False,
+        show_deleted_org_units: bool = False,
+        field_names: list[str] = None,
     ) -> None:
         # Prevent a circular import.
         from iaso.diffing import Differ, diffs_to_json
@@ -307,10 +307,34 @@ def create_json_diff(
             if diff.status in count_status:
                 count_status[diff.status] += 1
 
+        # Keep track of the parameters used for the diff.
+        differ_config = {
+            # Version to update.
+            "version": self.source_version_to_update.pk,
+            "validation_status": source_version_to_update_validation_status,
+            "top_org_unit": source_version_to_update_top_org_unit.pk if source_version_to_update_top_org_unit else None,
+            "org_unit_types": [out.pk for out in source_version_to_update_org_unit_types]
+            if source_version_to_update_org_unit_types
+            else None,
+            # Version to compare with.
+            "version_ref": self.source_version_to_compare_with.pk,
+            "validation_status_ref": source_version_to_compare_with_validation_status,
+            "top_org_unit_ref": source_version_to_compare_with_top_org_unit.pk
+            if source_version_to_compare_with_top_org_unit
+            else None,
+            "org_unit_types_ref": [out.pk for out in source_version_to_compare_with_org_unit_types]
+            if source_version_to_compare_with_org_unit_types
+            else None,
+            # Options.
+            "ignore_groups": ignore_groups,
+            "show_deleted_org_units": show_deleted_org_units,
+            "field_names": field_names,
+        }
+
         self.count_create = count_status["new"]
         self.count_update = count_status["modified"]
         self.json_diff = diffs_to_json(diffs)
-        self.diff_config = str(differ_params)
+        self.diff_config = str(differ_config)
         self.save()
 
     def synchronize_source_versions(self):
diff --git a/iaso/tests/models/test_data_source_versions_synchronization.py b/iaso/tests/models/test_data_source_versions_synchronization.py
index 23f0389c5e..bc2ff57027 100644
--- a/iaso/tests/models/test_data_source_versions_synchronization.py
+++ b/iaso/tests/models/test_data_source_versions_synchronization.py
@@ -259,14 +259,14 @@ def test_create_json_diff(self):
 
         expected_diff_config = (
             "{"
-            f"'version': <SourceVersion: {str(self.source_version_to_update)}>, "
+            f"'version': {self.source_version_to_update.pk}, "
             f"'validation_status': '{m.OrgUnit.VALIDATION_VALID}', "
             "'top_org_unit': None, "
-            f"'org_unit_types': [<OrgUnitType: {str(self.org_unit_type_country)}>], "
-            f"'version_ref': <SourceVersion: {str(self.source_version_to_compare_with)}>, "
+            f"'org_unit_types': [{self.org_unit_type_country.pk}], "
+            f"'version_ref': {self.source_version_to_compare_with.pk}, "
             f"'validation_status_ref': '{m.OrgUnit.VALIDATION_VALID}', "
             "'top_org_unit_ref': None, "
-            f"'org_unit_types_ref': [<OrgUnitType: {str(self.org_unit_type_country)}>], "
+            f"'org_unit_types_ref': [{self.org_unit_type_country.pk}], "
             "'ignore_groups': True, "
             "'show_deleted_org_units': False, "
             "'field_names': ['name']"