That is a newer Graflex back. It's pretty thick. I would be surprised if your spring back would expand that far. You see the line along the base under the winder? That is a channel for the Graphics slides to move into and hold it against the back of the camera. I would just go for the 2x3 Grafmatic and use 6 sheets of film. But then again, that might not be what you want.
tim in san jose