Nice image. I tried to duplicate a National Park Service image of the siege gun at Drury's Bluff (Fort Darling) that overlooked the James River. Couldn't do it and I figured the photographer used a ladder to get the perspective that he did.
@Jimklag
As I recall it was off EmmitsBurg Road near the peach orchard. Took this a few years ago so I'm not 100% sure but it was facing east on the west side of where Pickett's charge was so this would be a confederate piece.