When I looked at a list (under construction) of Spanish American War Veteran Burials, I only found two names for Elmhurst Cemetery, both men were in the 3rd Illinois Volunteer Infantry.

(I don't know, if they are in the Cemetery Section in Question, but, I found further information for the two men on a roster list for the 3rd Ill. Vol. Inf.):

John W. Watling, Pvt. Co. "C" (residence in 1898 - Wen Lenox, Ill.,
buried - Elmhurst Cemetery, Joliet, Will Co., Illinois).

William Henry Malcolm, Cpl., 3rd Ill. Vol. Inf., Co. "M" (residence in 1898 - Kankakee, Ill. - July 22, 1872 / March 29, 1932 - buried - Elmhurst Cemetery, Joliet, Will Co., Illinois).

BTW - One of the men Culpeper found was also on the 3rd Ill. roster:

Jacob M. Muszynski, Pvt. Co. "A" (residence in 1898 - Chicago, Ill.).

It appears "Knute" found the answer with the Newspaper story: explaining the "United Spanish War Veterans - William McKinley Camp #6 - Chicago" likely purchasing a section in the Arlington Cemetery, for the burial of 'post' members.

I suppose any SAW Veterans, living around Chicago, in later life, would be eligible to join USWV - "Camp #6". This would explain different States and units being buried at this site.

FWIW - A brief 3rd. Illinois Vol. Inf. History:

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