Roger, first I would call Hollywood Cemetery and talk with them. Here is a link to the cemetery where you can get their phone number. http://www.hollywoodcemetery.org/

Here is a link to the application form for a free headstone provided by the US Government. http://www.cem.va.gov/pdf/401330.pdf

Here is a picture of the Gettysburg Dead section in Hollywood Cemetery. To the right you can see government headstones that have been installed. http://www.southernheritagephotos.com/gal_richmond1.htm

What unit was your ancestor in? Have you joined the Sons of Confederate Veterans?