Disclosed is an articulated harvesting combine of a forward power processing unit (PPU) having a forward set of wheel assemblies and a rear grain cart connected by an articulating joint assembly. Bonus sieves assemblies are located in the outer rear of the PPU for accepting grain from concaves and grates assemblies located forward of the bonus sieves assemblies. The bonus sieves assemblies accept tailings from the concaves and grates assemblies for additional separation of grain from material other than grain (MOG). New and separate airflow is provided for the bonus sieves. The bonus sieves tailings are returned to the bonus sieves for rethreshing, optionally after being particulated and air separation performed.