I am making my own grain mill patterned from "The Barley Crusher". I have a couple of questions about this mill. I have used these mills at my local store, but have never really "looked it over", and going to there website I cant make definite call on the roller spacing. I see the bottom roller is the only adjustable roller, which adjusts towards or away from the two top rollers, and making that is not a problem. I would like to know the spacing between the two top rollers?It appears that the two top rollers are not adjustable, that the only adjustment is the bottom roller. Is this correct? Anyone with information on these mills that can answer these questions would be greatly appreciated.