I have found that the best position to drill is to turn the prop facing you(forward) placing the prop on a horizontal plane. set the drill jig with one hole to the 1o clock position. drill from the front first, reverse the drill jig to the rear and then drill through from the back to true the holes. when putting the prop on the plane, set it as to compression comming to the 1:00 clock position. Ths will best insure fingers are clear on the downward swing of the prop.