Was conducting research into the monuments and memorials at Shiloh National Military Park (in particular, the Headquarters Monuments) and ran into an unexpected brick wall: although individual States paid for the creation of stone regimental markers and State participation markers at Shiloh, the States were not involved in creation and erection of the many Headquarters Monuments (memorializing brigade and division HQ locations at the commencement of the battle.) http://archive.org/details/illinoisatshiloh00illi Illinois at Shiloh was one of the resources consulted.
After a bit of searching, tracked down this reference, published in 2012: A History and Guide to the Monuments of Shiloh National Park, by Stacy W. Reaves. Only about forty pages long, this resource records the drive behind the establishment of the national military parks, and responsibility for all the memorials and monuments (especially those at Shiloh NMP.) Some excellent circa-1900 photographs are included. http://issuu.com/historypressusa/docs/4124-shiloh
Turns out, on pages 35 - 36 are to be found the answers to my questions IRT the Headquarters Monument. And it also turns out, Perry Cuskey introduced this book a few years ago (and it comes back as a "hit" when "monuments" is inserted in the Search Box.)
Ozzy