Possibly narrowed it down even further to the Ansco "Buster Brown" 2, 2A, or 3. There were slight variations in the carry strap location, Winder knob style and shutter release on the side, but seem to have used the same manual, lol
I've had this camera before and it's driving me NUTS! Have you taken the film guide out? A lot of times it has the camera make on a label on the outside of the guide along with the size of film it uses. I am going to keep looking for the exact model though.
On the side of your camera is a dial that advances the film. It will pull out and release the film guide. Try that and if it doesn't work let me know (but it should). I have only seen a couple of box cameras that need other steps to remove the film guide.