I recently purchased a 55 in very good condition. It is a square back, serial number 93803 H. I need some help identifying the year and a service manual/diagram that will show me the grain unloading auger mechanism (lever, pulley, chains, everything) in its entirety and how it should work. I cut wheat with it this year and it cleans grain very well. However, the grain unloading auger lever wouldn´t pull back all the way, and during unloading the chain jumped off, broke the two wooden guides and wedged the auger stuck. I was able to free the mechanism and get it moving again, but then I couldn´t disengage the auger. It jumped off the pulley twice and I gave up. I have an owners´manual, but it is obviously for an older model, as the picture of the unloading mechanism is quite different than mine. Any help would be greatly appreciated.