If you have some time, below is a link to a very good article. But if you don’t have the time, the meat of the article on combine settings is below.
If people ask about how to adjust the combine in a high-scab field: Research at the Ohio State University showed that adjusting the combine’s fan speed between 1,375 and 1,475 rpms and shutter opening to 90 mm (3.5 inches) resulted in the lowest discounts that would have been received at the elevator due to low test weight, % damaged kernels, and DON in the harvested grain (Salgado et al., 2011; PDF at http://plantpath.osu.edu/sites/plantpath/files/imce/files/Paul/PDIS-01-14-0093-RE.pdf)
Follow the below to help reduce vomitoxin in your wheat harvest.
Harvest Techniques To Reduce Fusarium Infected Kernels
Adjust combine so lightweight, shriveled kernels are also removed with chaff. The goal is to blow the lightweight, diseased kernels out the back of the combine without blowing out too many good kernels. This technique is feasible when the rest of the grain is of good quality. In fields severely affected by leaf diseases, the lower test weight of the grain may make it more difficult to separate normal kernels from Fusarium damaged kernels.
Source for above UGA extension