diff --git a/design_builder/contrib/ext.py b/design_builder/contrib/ext.py
index 5ddb6f4a..5ecb0926 100644
--- a/design_builder/contrib/ext.py
+++ b/design_builder/contrib/ext.py
@@ -11,7 +11,7 @@
 from nautobot.ipam.models import Prefix
 
 import netaddr
-from design_builder.design import INSTANCE_POST_SAVE, Builder
+from design_builder.design import Builder
 from design_builder.design import ModelInstance
 
 from design_builder.errors import DesignImplementationError
@@ -384,9 +384,10 @@ def __init__(self, object_creator: Builder):
             )
 
     @staticmethod
-    def _post_save(model_instance: ModelInstance, **kwargs) -> None:
-        endpoint_a = model_instance.instance.endpoint_a
-        endpoint_z = model_instance.instance.endpoint_z
+    def _post_save(sender, **kwargs) -> None:
+        peering_instance: ModelInstance = sender
+        endpoint_a = peering_instance.instance.endpoint_a
+        endpoint_z = peering_instance.instance.endpoint_z
         endpoint_a.peer, endpoint_z.peer = endpoint_z, endpoint_a
         endpoint_a.save()
         endpoint_z.save()
@@ -461,5 +462,6 @@ def attribute(self, value, model_instance) -> None:
         retval["endpoints"] = [endpoint_a, endpoint_z]
         endpoint_a.attributes["peering"] = model_instance
         endpoint_z.attributes["peering"] = model_instance
-        model_instance.connect(INSTANCE_POST_SAVE, BGPPeeringExtension._post_save)
+
+        model_instance.connect(ModelInstance.POST_SAVE, BGPPeeringExtension._post_save)
         return retval
diff --git a/design_builder/design.py b/design_builder/design.py
index d1dcbc6d..04e9ee0e 100644
--- a/design_builder/design.py
+++ b/design_builder/design.py
@@ -98,11 +98,6 @@ def _map_query_values(query: Mapping) -> Mapping:
     return retval
 
 
-# Callback Event types
-INSTANCE_PRE_SAVE = Signal()
-INSTANCE_POST_SAVE = Signal()
-
-
 class ModelInstance:  # pylint: disable=too-many-instance-attributes
     """An individual object to be created or updated as Design Builder iterates through a rendered design YAML file."""
 
@@ -114,6 +109,10 @@ class ModelInstance:  # pylint: disable=too-many-instance-attributes
 
     ACTION_CHOICES = [GET, CREATE, UPDATE, CREATE_OR_UPDATE]
 
+    # Callback Event types
+    PRE_SAVE = Signal()
+    POST_SAVE = Signal()
+
     def __init__(
         self, creator: "Builder", model_class: Type[BaseModel], attributes: dict, relationship_manager=None, parent=None
     ):  # pylint:disable=too-many-arguments
@@ -233,7 +232,13 @@ def connect(self, signal: Signal, handler):
             signal: Signal to listen for.
             handler: Callback function
         """
-        signal.connect(handler, self.instance.pk)
+        dispatch_id = (
+            self.model_class._meta.app_label,
+            self.model_class._meta.model_name,
+            id(handler),
+        )
+
+        signal.connect(handler, self, dispatch_uid=dispatch_id)
 
     def _load_instance(self):
         query_filter = _map_query_values(self.filter)
@@ -310,7 +315,7 @@ def save(self):
         # ensure that parent instances have been saved and
         # assigned a primary key
         self._update_fields()
-        INSTANCE_PRE_SAVE.send(sender=self.instance.pk, model_instance=self)
+        ModelInstance.PRE_SAVE.send(sender=self)
         try:
             self.instance.full_clean()
             self.instance.save()
@@ -339,7 +344,7 @@ def save(self):
                 self.instance.refresh_from_db()
 
                 field.set_value(related_object.instance)
-        INSTANCE_POST_SAVE.send(sender=self.instance.pk, model_instance=self)
+        ModelInstance.POST_SAVE.send(sender=self)
 
     def set_custom_field(self, field, value):
         """Sets a value for a custom field."""