diff --git a/ui/core/mirage/serializers/application.js b/ui/core/mirage/serializers/application.js
index 1c3821b4b..7bfbc7cd7 100644
--- a/ui/core/mirage/serializers/application.js
+++ b/ui/core/mirage/serializers/application.js
@@ -32,6 +32,12 @@ export default RestSerializer.extend({
     return underscore(attr);
   },
 
+  keyForRelationshipId(relationshipName) {
+    return `${this._container.inflector.singularize(
+      underscore(relationshipName)
+    )}_id`;
+  },
+
   /**
    * Serialize items into a root key `items`.
    * @return {object}
@@ -43,6 +49,22 @@ export default RestSerializer.extend({
     return json;
   },
 
+  /**
+   * Serialize scope into the payload, if set.
+   * @param {object} model
+   * @return {object}
+   */
+  _hashForModel(model) {
+    const json = RestSerializer.prototype._hashForModel.apply(this, arguments);
+    if (model.scope) {
+      json.scope = {
+        id: model.scope.id,
+        type: model.scope.type
+      };
+    }
+    return json;
+  },
+
   /**
    * Adds a root to the payload, since `root: false` doesn't appear to affect
    * the normalize method.
diff --git a/ui/core/mirage/serializers/auth-method.js b/ui/core/mirage/serializers/auth-method.js
index 3d0c37374..cabe9ee7b 100644
--- a/ui/core/mirage/serializers/auth-method.js
+++ b/ui/core/mirage/serializers/auth-method.js
@@ -1,22 +1,5 @@
 import ApplicationSerializer from './application';
-import { underscore } from '@ember/string';
 
 export default ApplicationSerializer.extend({
-  modelName: 'auth-method',
-
-  keyForRelationshipId(relationshipName) {
-    return `${this._container.inflector.singularize(
-      underscore(relationshipName)
-    )}_id`;
-  },
-
-  _hashForModel(model) {
-    const json = ApplicationSerializer.prototype._hashForModel.apply(this, arguments);
-    json.scope = {
-      id: model.scope.id,
-      type: model.scope.type
-    };
-    return json;
-  }
-
+  modelName: 'auth-method'
 });
diff --git a/ui/core/mirage/serializers/group.js b/ui/core/mirage/serializers/group.js
index ca0f9b138..2854224f8 100644
--- a/ui/core/mirage/serializers/group.js
+++ b/ui/core/mirage/serializers/group.js
@@ -10,19 +10,9 @@ export default ApplicationSerializer.extend({
     )}_ids`;
   },
 
-  keyForRelationshipId(relationshipName) {
-    return `${this._container.inflector.singularize(
-      underscore(relationshipName)
-    )}_id`;
-  },
-
   _hashForModel(model) {
     const json = ApplicationSerializer.prototype._hashForModel.apply(this, arguments);
     json.member_ids = model.memberIds;
-    json.scope = {
-      id: model.scope.id,
-      type: model.scope.type
-    };
     return json;
   }
 
diff --git a/ui/core/mirage/serializers/host-catalog.js b/ui/core/mirage/serializers/host-catalog.js
index 34277f96e..bab3f7aa0 100644
--- a/ui/core/mirage/serializers/host-catalog.js
+++ b/ui/core/mirage/serializers/host-catalog.js
@@ -1,22 +1,5 @@
 import ApplicationSerializer from './application';
-import { underscore } from '@ember/string';
 
 export default ApplicationSerializer.extend({
   modelName: 'host-catalog',
-
-  keyForRelationshipId(relationshipName) {
-    return `${this._container.inflector.singularize(
-      underscore(relationshipName)
-    )}_id`;
-  },
-
-  _hashForModel(model) {
-    const json = ApplicationSerializer.prototype._hashForModel.apply(this, arguments);
-    json.scope = {
-      id: model.scope.id,
-      type: model.scope.type
-    };
-    return json;
-  }
-
 });
diff --git a/ui/core/mirage/serializers/host-set.js b/ui/core/mirage/serializers/host-set.js
index 16d665375..bd680326e 100644
--- a/ui/core/mirage/serializers/host-set.js
+++ b/ui/core/mirage/serializers/host-set.js
@@ -10,20 +10,10 @@ export default ApplicationSerializer.extend({
     )}_ids`;
   },
 
-  keyForRelationshipId(relationshipName) {
-    return `${this._container.inflector.singularize(
-      underscore(relationshipName)
-    )}_id`;
-  },
-
   _hashForModel(model) {
     const json = ApplicationSerializer.prototype._hashForModel.apply(this, arguments);
     json.host_ids = model.hostIds;
     json.host_catalog_id = model.hostCatalogId;
-    json.scope = {
-      id: model.scope.id,
-      type: model.scope.type
-    };
     return json;
   }
 
diff --git a/ui/core/mirage/serializers/host.js b/ui/core/mirage/serializers/host.js
index 4fb0353b4..ccd3994ca 100644
--- a/ui/core/mirage/serializers/host.js
+++ b/ui/core/mirage/serializers/host.js
@@ -1,22 +1,5 @@
 import ApplicationSerializer from './application';
-import { underscore } from '@ember/string';
 
 export default ApplicationSerializer.extend({
-  modelName: 'host',
-
-  keyForRelationshipId(relationshipName) {
-    return `${this._container.inflector.singularize(
-      underscore(relationshipName)
-    )}_id`;
-  },
-
-  _hashForModel(model) {
-    const json = ApplicationSerializer.prototype._hashForModel.apply(this, arguments);
-    json.scope = {
-      id: model.scope.id,
-      type: model.scope.type
-    };
-    return json;
-  }
-
+  modelName: 'host'
 });
diff --git a/ui/core/mirage/serializers/role.js b/ui/core/mirage/serializers/role.js
index 47623471d..159bdc56c 100644
--- a/ui/core/mirage/serializers/role.js
+++ b/ui/core/mirage/serializers/role.js
@@ -1,18 +1,10 @@
 import ApplicationSerializer from './application';
-import { underscore } from '@ember/string';
 
 export default ApplicationSerializer.extend({
   modelName: 'role',
 
-  keyForRelationshipId(relationshipName) {
-    return `${this._container.inflector.singularize(
-      underscore(relationshipName)
-    )}_id`;
-  },
-
   _hashForModel(model) {
     const json = ApplicationSerializer.prototype._hashForModel.apply(this, arguments);
-    
     const serializedUsers = model.users.models.map(user => ({
       scope_id: model.scope.id,
       id: user.id,
@@ -24,12 +16,6 @@ export default ApplicationSerializer.extend({
       type: 'group'
     }));
     json.principals = [ ...serializedUsers, ...serializedGroups ];
-
-    json.scope = {
-      id: model.scope.id,
-      type: model.scope.type
-    };
-
     return json;
   }
 });
diff --git a/ui/core/mirage/serializers/target.js b/ui/core/mirage/serializers/target.js
index 8ced88cfc..c9c6935a0 100644
--- a/ui/core/mirage/serializers/target.js
+++ b/ui/core/mirage/serializers/target.js
@@ -10,12 +10,6 @@ export default ApplicationSerializer.extend({
     )}_ids`;
   },
 
-  keyForRelationshipId(relationshipName) {
-    return `${this._container.inflector.singularize(
-      underscore(relationshipName)
-    )}_id`;
-  },
-
   _hashForModel(model) {
     const json = ApplicationSerializer.prototype._hashForModel.apply(this, arguments);
     const { hostSets } = this.schema;
@@ -24,10 +18,6 @@ export default ApplicationSerializer.extend({
       const host_catalog_id = hostSet?.hostCatalog?.id;
       return { host_set_id, host_catalog_id };
     });
-    json.scope = {
-      id: model.scope.id,
-      type: model.scope.type
-    };
     return json;
   }
 
diff --git a/ui/core/mirage/serializers/user.js b/ui/core/mirage/serializers/user.js
index 499b249eb..142cbf508 100644
--- a/ui/core/mirage/serializers/user.js
+++ b/ui/core/mirage/serializers/user.js
@@ -1,22 +1,5 @@
 import ApplicationSerializer from './application';
-import { underscore } from '@ember/string';
 
 export default ApplicationSerializer.extend({
-  modelName: 'user',
-
-  keyForRelationshipId(relationshipName) {
-    return `${this._container.inflector.singularize(
-      underscore(relationshipName)
-    )}_id`;
-  },
-
-  _hashForModel(model) {
-    const json = ApplicationSerializer.prototype._hashForModel.apply(this, arguments);
-    json.scope = {
-      id: model.scope.id,
-      type: model.scope.type
-    };
-    return json;
-  }
-
+  modelName: 'user'
 });