Data tag would refer to the original army tag, that's right. Most of the "45"s were re-branded with a different plate and painted black for sales into the civilian market so finding an army tag is pretty neat.
From one info page: "[COLOR=#ffff00]Camera, Combat[/COLOR] (Combat Graphic). Special US Navy and Marine Corps 4" x 5" wooden body camera designed for the Pacific war. Marine Corps version in OD green, Navy versions in OD green or battleship grey. All have black Supermatic shutter/ Kodak Anastigmat Special f4.7 127mm focusing lens with 'EExxxx' serial number. Official military metal plate attached to shutter winding side of camera body. After WW2 some were painted black and sold on the civilian market as 'Graphic 45' cameras. Only about 1500 made."
I don't think that they're a collector's item at all, just an oddity from the later years of the war. My wood shell is in good shape, but the in-lens shutter is mostly non functional and only shoots at one speed. Plus someone back in the mists of time retrofit a graflok back to it, replacing the original spring back. I'm torn between un-fitting the new back to "restore" it to original or leaving it there because it too is now a part of history.