Actually, the lock-down screw is the odd one out as it has a tiny head on it - which may be machined down at the factory. The two outside screws only push the nut up so they look like below (not sure the point is a stock thing or also machined in-house). If you need to raise your nut think about just loosening the lock-down screw and shimming it with something very thin, preferably metal. That could work.
Jimmy J
