First, this primarily applies to high trackers. If your PAP horizontal component is less than about 5" and your vertical component is 0 or positive I wouldn't worry about it. Maybe a better way to think of it is that you want the track's bowtie to be above the fingers. To estimate where that bowtie will be, draw a line from the PAP through the pin to the track. There's a web site that has a drawing showing the safe zone, but I haven't been able to find it, maybe someone reading this can direct us there. -- JohnP