What updates are avalible for a 1987 1680 combine? Also were they a good combine compared to a 1990-1994 1680 or 1688? Is it possible to do peas with them or would one in a newer year be better. I am looking at about 900-1500 acres of cereals, canola, oats, barley, wheat, and some peas. What are the down falls to this combine?