Avoid dispatch_to_index_op in a couple places

Author: jbrockmendel

pandas/core/ops/__init__.py

@@ -1096,12 +1096,13 @@ def wrapper(self, other, axis=None):
         elif is_datetime64_dtype(self) or is_datetime64tz_dtype(self):
             # Dispatch to DatetimeIndex to ensure identical
             # Series/Index behavior
-
-            res_values = dispatch_to_index_op(op, self, other, pd.DatetimeIndex)
+            from pandas.core.arrays import DatetimeArray
+            res_values = dispatch_to_extension_op(op, DatetimeArray(self), other)
             return self._constructor(res_values, index=self.index, name=res_name)
 
         elif is_timedelta64_dtype(self):
-            res_values = dispatch_to_index_op(op, self, other, pd.TimedeltaIndex)
+            from pandas.core.arrays import TimedeltaArray
+            res_values = dispatch_to_extension_op(op, TimedeltaArray(self), other)
             return self._constructor(res_values, index=self.index, name=res_name)
 
         elif is_extension_array_dtype(self) or (