We're having a hard time making good straw out of our 1666. We got it last year for beans and corn, so this is the first time we've used it in wheat. Currently in it are two small wire concaves (first two) and a large wire. Smooth/slotted grates are in the back. The header is a 17'6" 1020, and the wheat ranges from 100+bu/ac patches to killed out (wet year) with most average around 75bu/ac. The grain sample is okay but have issues getting the grain loss monitor to stay in the green. I had read on here about people taking out every other knife in the chopper, and was wondering if that would be of any benefit. So far this year the straw has been very tough, so I'm not sure it would help or not. We're in central Ontario. Any suggestions would be appreciated.