I have a GP 1006 and love it. To start planting first I run 10' with the drill an inch off the ground to check that every row is planting and seed spacings, then I set the depth and plant about a hundred feet and check the seed depth. I find that about every different field condition might take a different depth adjustment, and a visual check of the amount of seed on top of the ground is my gauge that tells me to set it deeper or shallower. The optimum setting for me is when I see a few seeds on top of the ground, but not a lot. I usually plant soybeans about 1 3/4" deep, at 1 1/4" I'd also have more on top than I'd be comfortable with. Soybean seeds on top of the ground won't germinate unless they are in a furrow where a heavy rain storm will bury them. Your seed cup settings won't effect the planting depth, but the angle of your drill from front to back according to your hitch adjustments, as to whether the drill is level or tilted front or back will change the seed depth and change the efficiency of the row openers and closers. The drill needs to be level front to back and side to side. It should have a rack on the front of the seed box for suitcase weights if needed, although I never needed extra weight on mine.