If you're looking for an Illinois unit's morning reports, I would expect to find them at the Illinois state archives. If they do have these at the USAMHI, it is news to me.
I'm adding this after more looking. According to the USAMHI website they do not have the morning reports and say these are at the NARA, but I do know the state of Illinois and Pennsylvania have these, as well. I presume other states do also.
If you'll tell me what you're looking for, I'll have my NARA guy take a peek.