I wish it were that easy. We can reasonably be certain it was a Virginia regiment in Pickett's charge, but the three brigades were jumbled together at the point of attack. A few Confederates broke through to attack Cowan behind the Federal units crowded at the angle. My best guess: it could be a left or center regiment of Kemper's brigade (3, 7 or 1 VA), a right regiment of Garnett's (18 or 8 VA), or a right or center regiment of Armistead's brigade (53, 9, or 14 VA). That "narrows" it down to eight regiments.