Before I order any parts what updates or changes can or should I look for. The rotors in it now have 3 sets of rasp bars and the long solid fins on the rear. Seems to me that the later machines had some agitators on the rotors. Can I put those on my rotors and what other machines have the same internals as my TR 86? Need a right hand concave and extension. Use it mostly for soybeans but run corn now and then and a wee bit of barley each year. Thanks for any advice!