Really....7.5% out. OMG. Return it. You pay the shipping back to them. (Return shipping isn't free) than you can go buy a full price one locally and inspect it before you pay for it. That way it will meet your quality control. Or you can realize its 92.5% correct( probably better than most of us did on our last test) and live with it.
Sometimes one has to realize the person at the other might be a paper pusher whose never even started a tractor let alone install or used an implement. They sometimes say something off the wall. Just roll your eyes and move on. Don't come here and bash them for some unimportant issue. Start a tread when they really screwed up.
I have to go now because I bent my boxblade end plate, the deflection is greater than the allowable 9.32% deviation. I'll just replace it.