try it for yourself! every time i try it just sellects the HQ im clicking on so i cant hit "attach"
I tryed it and I don't think it's possible.
Click on one Devisional HQ. Than open the HQ menu and navigete with < > buttons to Corps HQ. Attach button doesn't show.
This HQ attachment is possible on World At War games. You can get them at
www.the-underdogs.info