Richard (and other discussion amigos)
I know that the plaque at G'burg follows the line of Frassanito's argument about the body being "posed" at the rock formation after earlier "downhill" shots.
See the link below to discover the weakness of that position and the pretty well established proof that it was the other way around. The famous photo shows the body in its original position -- then the photographers moved it downhill for the other shots.
There's also written testimony from a Union captain to support the original position with eyewitness (and right-after-the-battle) account. What evidence does Frassanito give that the body was posed at the rocks? Answer -- none.
The G'burg park has also been early to associate Henry Clay Powell as the owner of the sharpshooter/target rifle in their museum (initials HCP carved into it). Other than the coincidence of initials, there is no proof of connection. The Natl Park Service is often too quick to "conclude" matters.