Of course, it's not the most accurate method, but you can find approximate PAP location by putting a piece of tape where you think your PAP is, and then throw the ball. See if the piece of tape stays in one place as the ball goes down the first few feet of the lane. (It will move when the ball flares later down lane, don't worry about that). If the piece of tape stays in place, that's your PAP. If it moves, it's not. Try moving the piece of tape and see what happens then.