How do I Ad-Hoc Combined Courses

In Campus Solutions:

ANTH4020-005 is a combined section with ANTH5020-005

and

ANTH4020-006 is a combined section with ANTH5020-006

I need all four of these courses to be ad-hoc'ed together.

When I make the changes that I normally do to ad-hoc courses that do not have combined sections (i.e. remove the IMS Association Numbers for all four sections), I still get this error:

Class section(s) [23289, 24374] cannot be associated because they already participate in a class association.

Remove the section association(s) and re-save the page or remove the existing section association(s).

Can someone give me some details on how I can accomplish this?