I have an old international 56 4 row planter, I would like to plant chufa with. Right now I have the soybean 3 plates which I know are to small. My dilemma is should I order the soybean 1 plates or the soybean 2 plates. The soybean 1 plates are the largest. By any chance does anyone have any experience in this to save me from ordering both sets and sending one back. I have the dimensions of the opening on each plate but have not been able to find the average size of chufa and my chufa has not come in to the seed store yet. Any help would be greatly appreciated.