I recently acquired a JD1240 and I'm having troubles finding the plates I'm needing to plant soybeans. (Yes its a 1240 plate planter) Everything I'm finding is for Corn. I would like to use the Lustran plates if possible but I don't know how to set the sprockets for the correct seed rate. I'm wanting to plant at 50 lb per acre. With the seed I have that should be around 136,000. I've scoured the web trying to find the answer and all I've found is to use the B2 plate but that is a flat corn plate and also doesn't tell the sprocket settings. I know that Lincoln has plates but I don't want to drop $65 a plate on this 1240 because if I find a 7000 close to me for a reasonable price I'll try to pick it up. But for now its the 1240 to get the beans in. If anyone can help it would be much appreciated.