diff --git a/jwst/assign_wcs/util.py b/jwst/assign_wcs/util.py
index d8e492587f..4a624543c3 100644
--- a/jwst/assign_wcs/util.py
+++ b/jwst/assign_wcs/util.py
@@ -127,7 +127,7 @@ def compute_scale(wcs: WCS, fiducial: Union[tuple, np.ndarray],
     if spectral and disp_axis is None:
         raise ValueError('If input WCS is spectral, a disp_axis must be given')
 
-    crpix = np.array(wcs.invert(*fiducial))
+    crpix = np.array(wcs.invert(*fiducial, with_bounding_box=False))
 
     delta = np.zeros_like(crpix)
     spatial_idx = np.where(np.array(wcs.output_frame.axes_type) == 'SPATIAL')[0]
diff --git a/jwst/resample/resample_utils.py b/jwst/resample/resample_utils.py
index c527b450f1..39cdeba53e 100644
--- a/jwst/resample/resample_utils.py
+++ b/jwst/resample/resample_utils.py
@@ -4,6 +4,7 @@
 
 import numpy as np
 from astropy import units as u
+from astropy import wcs as fitswcs
 import gwcs
 
 from stdatamodels.dqflags import interpret_bit_flags
@@ -157,21 +158,40 @@ def reproject(wcs1, wcs2):
         positions in ``wcs1`` and returns x, y positions in ``wcs2``.
     """
 
-    try:
-        forward_transform = wcs1.pixel_to_world_values
-        backward_transform = wcs2.world_to_pixel_values
-    except AttributeError as err:
-        raise TypeError("Input should be a WCS") from err
+    # try:
+    #     # forward_transform = wcs1.pixel_to_world_values
+    #     # backward_transform = wcs2.world_to_pixel_values
+    #     forward_transform = wcs1.forward_transform
+    #     backward_transform = wcs2.backward_transform
+    # except AttributeError as err:
+    #     raise TypeError("Input should be a WCS") from err
+    def _get_forward(wcs):
+        if isinstance(wcs, gwcs.WCS):
+            return wcs.forward_transform
+        elif isinstance(wcs, fitswcs.WCS):
+            return wcs.pixel_to_world
+        elif isinstance(wcs, Model):
+            return wcs
+
+    def _get_backward(wcs):
+        if isinstance(wcs, gwcs.WCS):
+            return wcs.backward_transform
+        elif isinstance(wcs, fitswcs.WCS):
+            return wcs.world_to_pixel
+        elif isinstance(wcs, Model):
+            return wcs
 
     def _reproject(x, y):
-        sky = forward_transform(x, y)
+        #sky = forward_transform(x, y)
+        sky = _get_forward(wcs1)(x, y)
         flat_sky = []
         for axis in sky:
             flat_sky.append(axis.flatten())
         # Filter out RuntimeWarnings due to computed NaNs in the WCS
         with warnings.catch_warnings():
             warnings.simplefilter("ignore", RuntimeWarning)
-            det = backward_transform(*tuple(flat_sky))
+            #det = backward_transform(*tuple(flat_sky))
+            det = _get_backward(wcs2)(*tuple(flat_sky))
         det_reshaped = []
         for axis in det:
             det_reshaped.append(axis.reshape(x.shape))
diff --git a/jwst/resample/tests/test_utils.py b/jwst/resample/tests/test_utils.py
index 7e7deb3070..518fc61998 100644
--- a/jwst/resample/tests/test_utils.py
+++ b/jwst/resample/tests/test_utils.py
@@ -38,7 +38,7 @@ def wcs_gwcs():
     crpix = (500.0, 500.0)
     shape = (1000, 1000)
     pscale = 0.06 / 3600
-    
+
     prj = astmodels.Pix2Sky_TAN()
     fiducial = np.array(crval)
 
@@ -193,7 +193,7 @@ def test_reproject(wcs1, wcs2, offset, request):
     wcs1 = request.getfixturevalue(wcs1)
     wcs2 = request.getfixturevalue(wcs2)
     x = np.arange(150, 200)
-    
+
     f = reproject(wcs1, wcs2)
     res = f(x, x)
     assert_allclose(x, res[0] + offset)
diff --git a/jwst/tweakreg/tests/test_multichip_jwst.py b/jwst/tweakreg/tests/test_multichip_jwst.py
index 4402f7b897..b8e2f1a08a 100644
--- a/jwst/tweakreg/tests/test_multichip_jwst.py
+++ b/jwst/tweakreg/tests/test_multichip_jwst.py
@@ -81,7 +81,7 @@ def _make_gwcs_wcs(fits_hdr):
              Mapping((1, 2), name='xtyt'))
     c2tan.name = 'Cartesian 3D to TAN'
 
-    tan2c = (Mapping((0, 0, 1), n_inputs=2, name='xtyt2xyz') |
+    tan2c = (Mapping((0, 0, 1), name='xtyt2xyz') |
              (Const1D(1, name='one') & Identity(2, name='I(2D)')))
     tan2c.name = 'TAN to cartesian 3D'
 
@@ -376,7 +376,8 @@ def test_multichip_alignment_step_rel(monkeypatch):
         format='ascii.ecsv', delimiter=' ',
         names=['RA', 'DEC']
     )
-    x, y = wr.world_to_pixel(refcat['RA'], refcat['DEC'])
+    #x, y = wr.world_to_pixel(refcat['RA'].value, refcat['DEC'].value)
+    x, y = wr.invert(refcat['RA'].value, refcat['DEC'].value,  with_bounding_box=False)
     refcat['x'] = x
     refcat['y'] = y
     mr.tweakreg_catalog = refcat
@@ -459,7 +460,8 @@ def test_multichip_alignment_step_abs(monkeypatch):
         format='ascii.ecsv', delimiter=' ',
         names=['RA', 'DEC']
     )
-    x, y = wr.world_to_pixel(refcat['RA'], refcat['DEC'])
+    #x, y = wr.world_to_pixel(refcat['RA'], refcat['DEC'])
+    x, y = wr.invert(refcat['RA'].value, refcat['DEC'].value, with_bounding_box=False)
     refcat['x'] = x
     refcat['y'] = y
     mr.tweakreg_catalog = refcat