Draw a line from the middle of your thumb hole through the middle of your bridge, this is the grip centerline. Now locate your grip center, midway between the edge of the thumb hole and the average position of the edges of your finger holes (eliminating the bevel on all holes). Now draw a line perpendicular to the centerline through the grip center, this is your grip midline. With the ball aligned so the thumb hole is down and the finger holes are up, measure across the midline 4" to the right (for a right hander) to the vertical axis line (VAL). Now measure UP the VAL the 7/8" and you've located your PAP. If your track was inverted the measurement would be DOWN the VAL. This distance has nothing to do with axis tilt, tilt is dependent only on the diameter of the initial track ring. -- JohnP
