Pete,
I figured you'd know about the Longacre shots. Sam Harrison has well over one hundred shots from his father that he uploaded to Flickr. They are different that most of the Longacre shots in that they are mainly snapshots (the Longacre shots are more "professional"). They are different, but valuable in their own right to give you an idea of service through the eyes of the "normal joe". His shots can be viewed at:
https://www.flickr.com/photos/129969616@N08/
I actually found a photo that shows the "motor pool gang" which has my grandfather in it (which is very cool since we have no other photos of him during his time in Europe). He was assigned to A Company through his time at Camp Butner, but was transferred to H&S Company right before deployment. He was subsequently transferred back to A Company sometime in January 1945 "due to a shortage of mechanics" and stayed assigned to that company the rest of his time in the service.
All of my pictures on Flickr are already hi-res scans and can be downloaded at their full size from the site. I actually scanned the front and the writing on the back of each picture and made it one *.tif file, with two images inside. Those Tiff files are pretty big. If anybody wants those "original" full quality scans with front and back, I can gladly send them to you. I think in total they're around 2GB or 3GB. Easily fit on a flash drive in the mail. I've got a video interview with my grandpa from 2013-2014 before he passed. I haven't been able to edit it yet, but I'm hoping to tackle that soon. Hopefully that can add to the history mystery too.
-SaM