@Bentley, I am eyeing one of the backs for rollfilm it says Graflex 3.25x4.25 on the mount flange. How does the 6x9 relates to what you see on the ground glass. Are there lines I need to use to compensate?
Get a piece of mylar, place it in the opening of your roll film holder and mark it with a sharpie. Using the back installed but the roll film holder not on it, figure out how to place the mylar on top of the viewing glass (in the reflex hood) to match the rectangle drawn on the mylar with what you see through the hole in your roll film holder. Tape the mylar onto the viewing glass inside the hood.