You have a 1960 model. The early models were round backs and the later ones were square backs. I have 2 round backs and 1 square. The early ones only had 1 brake pedal. I don't know about the trash spinner on the back, my square back has one but I think it was added. If you are going to use it much, I would put an electric fuel pump on it. We did this and they can sit in the shed for a year and start right up with a fresh battery. They are a fun little combine and can be hauled on a gooseneck trailer. BTW, the 40 was made from 1960 - 1965. Mark