Although the information appears impressive, a modern day research by historians and battlefield guides argues that the number of burials shown on the map [in particular in the Rose Farm area] are much less in number than what actually exists.
The Library of Congress has an online and interactive Elliot Map. This link will bring you to the LOC map. Once you have the map on screen you can zoom in and out and scroll around the map by using the computer's mouse wheel. The Battle of Gettysburg Resource Center has a online compendium of historic and contemporary maps. Here is the link.