diff --git a/simpeg_drivers/components/models.py b/simpeg_drivers/components/models.py
index be91a6f4..0650807e 100644
--- a/simpeg_drivers/components/models.py
+++ b/simpeg_drivers/components/models.py
@@ -276,9 +276,9 @@ def lower_bound(self) -> np.ndarray | None:
             bound_model = -self._upper_bound.model
 
         if bound_model is None:
-            return -np.inf
-
-        lbound = bound_model.copy()
+            lbound = np.full(self.n_active, -np.inf)
+        else:
+            lbound = bound_model.copy()
 
         if self.is_sigma:
             is_finite = np.isfinite(lbound)
@@ -304,9 +304,9 @@ def upper_bound(self) -> np.ndarray | None:
             bound_model = self._upper_bound.model
 
         if bound_model is None:
-            return np.inf
-
-        ubound = bound_model.copy()
+            ubound = np.full(self.n_active, np.inf)
+        else:
+            ubound = bound_model.copy()
 
         if self.is_sigma:
             is_finite = np.isfinite(ubound)
diff --git a/simpeg_drivers/utils/regularization.py b/simpeg_drivers/utils/regularization.py
index 506b30c8..5d06a3ef 100644
--- a/simpeg_drivers/utils/regularization.py
+++ b/simpeg_drivers/utils/regularization.py
@@ -510,9 +510,13 @@ def set_rotated_operators(
     )
 
     grad_op_active = mesh.Pac.T @ (unit_grad_op @ mesh.Pac)
+
+    # Remove extra partial volume from missing neighbors
+    row_sum = np.asarray(grad_op_active.sum(axis=1)).ravel()
+    grad_op_active -= sdiag(row_sum)
+
     vol_avg_op = mesh.Pac.T @ (vol_avg_op @ mesh.Pac)
-    active_faces = np.isclose(grad_op_active @ np.ones(mesh.n_cells), 0)
-    active_faces &= grad_op_active.max(axis=1).toarray().ravel() != 0
+    active_faces = grad_op_active.max(axis=1).toarray().ravel() != 0
 
     vol_avg_op = vol_avg_op[active_faces, :]
     vol_avg_op = sdiag(np.asarray(vol_avg_op.sum(axis=1)).ravel() ** -1) @ vol_avg_op
diff --git a/tests/run_tests/driver_2d_rotated_gradients_test.py b/tests/run_tests/driver_2d_rotated_gradients_test.py
index 582f6132..5d6be39f 100644
--- a/tests/run_tests/driver_2d_rotated_gradients_test.py
+++ b/tests/run_tests/driver_2d_rotated_gradients_test.py
@@ -42,7 +42,7 @@
 # To test the full run and validate the inversion.
 # Move this file out of the test directory and run.
 
-target_run = {"data_norm": 0.6464643069717512, "phi_d": 1160, "phi_m": 5.29}
+target_run = {"data_norm": 0.6464643069717512, "phi_d": 1150, "phi_m": 5.37}
 
 
 def test_dc2d_rotated_grad_fwr_run(
@@ -52,7 +52,7 @@ def test_dc2d_rotated_grad_fwr_run(
     refinement=(4, 6),
 ):
     filepath = Path(tmp_path) / "inversion_test.ui.geoh5"
-    with Workspace.create(filepath) as geoh5:
+    with get_workspace(filepath) as geoh5:
         # Run the forward
         components = SyntheticsComponents(
             geoh5=geoh5,
diff --git a/tests/run_tests/driver_dc_b2d_rotated_gradients_test.py b/tests/run_tests/driver_dc_b2d_rotated_gradients_test.py
index 203f437e..96d53142 100644
--- a/tests/run_tests/driver_dc_b2d_rotated_gradients_test.py
+++ b/tests/run_tests/driver_dc_b2d_rotated_gradients_test.py
@@ -49,7 +49,7 @@
 # To test the full run and validate the inversion.
 # Move this file out of the test directory and run.
 
-target_run = {"data_norm": 1.1060093911270892, "phi_d": 208, "phi_m": 0.468}
+target_run = {"data_norm": 1.1060093911270892, "phi_d": 209, "phi_m": 0.468}
 
 
 def test_dc_rotated_p3d_fwr_run(
diff --git a/tests/run_tests/driver_grav_test.py b/tests/run_tests/driver_grav_test.py
index 3dc48539..67309a32 100644
--- a/tests/run_tests/driver_grav_test.py
+++ b/tests/run_tests/driver_grav_test.py
@@ -37,6 +37,8 @@
 from tests.utils.targets import check_target, get_inversion_output, get_workspace
 
 
+# pylint: disable=no-member
+
 # To test the full run and validate the inversion.
 # Move this file out of the test directory and run.
 target_run = {"data_norm": 0.0028055270497087128, "phi_d": 8.24e-06, "phi_m": 0.0234}
@@ -161,7 +163,7 @@ def test_gravity_run(
     driver = GravityInversionDriver.start(str(tmp_path / "Inv_run.ui.json"))
 
     assert driver.params.data_object.uid != gz.parent.uid
-    assert driver.models.upper_bound is np.inf
+    assert np.all(np.isinf(driver.models.upper_bound))
 
     with Workspace(driver.params.geoh5.h5file) as run_ws:
         output = get_inversion_output(
diff --git a/tests/run_tests/driver_joint_pgi_homogeneous_test.py b/tests/run_tests/driver_joint_pgi_homogeneous_test.py
index 43a7cc8b..aff3e37d 100644
--- a/tests/run_tests/driver_joint_pgi_homogeneous_test.py
+++ b/tests/run_tests/driver_joint_pgi_homogeneous_test.py
@@ -54,7 +54,7 @@
 # To test the full run and validate the inversion.
 # Move this file out of the test directory and run.
 
-target_run = {"data_norm": 390.70695894864303, "phi_d": 2020, "phi_m": 8.98}
+target_run = {"data_norm": 390.70695894864303, "phi_d": 2030, "phi_m": 9.23}
 INDUCING_FIELD = (50000.0, 90.0, 0.0)
 
 
diff --git a/tests/run_tests/driver_mvi_test.py b/tests/run_tests/driver_mvi_test.py
index b76caa91..35b01546 100644
--- a/tests/run_tests/driver_mvi_test.py
+++ b/tests/run_tests/driver_mvi_test.py
@@ -45,7 +45,7 @@
 # To test the full run and validate the inversion.
 # Move this file out of the test directory and run.
 
-target_mvi_run = {"data_norm": 149.10117434016038, "phi_d": 1070, "phi_m": 0.129}
+target_mvi_run = {"data_norm": 149.10117434016038, "phi_d": 1040, "phi_m": 0.129}
 
 
 def test_magnetic_vector_fwr_run(
diff --git a/tests/run_tests/driver_rotated_gradients_test.py b/tests/run_tests/driver_rotated_gradients_test.py
index be4f32a2..145372e2 100644
--- a/tests/run_tests/driver_rotated_gradients_test.py
+++ b/tests/run_tests/driver_rotated_gradients_test.py
@@ -40,8 +40,9 @@
 
 # To test the full run and validate the inversion.
 # Move this file out of the test directory and run.
+# pylint: disable=no-member
 
-target_run = {"data_norm": 0.4076195420139727, "phi_d": 37.5, "phi_m": 427}
+target_run = {"data_norm": 0.4076195420139727, "phi_d": 35.5, "phi_m": 432}
 
 
 def test_gravity_rotated_grad_fwr_run(