Dried down, windrowed bean vines are very tough, and the agitator pins are like clubs instead of cutters when you're in them. No specific configuration I can think of, but they need to be like brand new. (clean hex shape) You might consider bolting a few sickle sections to the bracing on your rear grates and let them protrude thru. I've done this on a couple of Case IHC with keystock grates in ropy, green soybean vines, and it seemed to help a lot.