G'Day Would think that you would need to close up the front of your concave to around 1_8 of an inch (3 mm)! this measurement is read when you have the concave closed right down and the top back check bar is touching the the highest rasp bar make sure that, that bar your measuring is parallel to the rasp bar and the same goes for the front check bar as well. (Reset your concave gauge to 0 on the out side!!) You might want to check to see if you have any filler plates that came with the combine so you can add two to three in the first rows of check bars to help with threshing. To help in any cereals it might pay to install a 2 inch O.D.(50mm) pvc (or somthing like it!) along the front just behind the knife but on top of the cutter bar to help trip up the wheat or barley heads, and so it feeds it in and under the table auger, this helps heaps with threshing!! (Heads hit concave first!!!!) I would try the concave downed pretty tight first, with no filler bars then play around from there! Try rotor Revs around 800-900 RPM's. Please let us know on how you got on!! Rolf PS: Don't!!!!!!! put any reverer bars back in! They should be placed on a shed shelf some were in the shed for you to walk past them all the time and look at and wonder how you could use them.