Jud Box has spent eight years coping with the death of his firefighter son at the World Trade Center — but that didn’t prepare him for what he saw posted to a new online archive of photos and videos about the Sept. 11 terrorist attacks. Scrolling through the archive, Box came face to face with his son, Gary Box, a firefighter with Brooklyn’s Squad 1, who was captured by a digital camera lugging his gear through a traffic-clogged Brooklyn-Battery Tunnel on his way to Ground Zero.