Be careful to insure the pin stays at least 1" away from the VAL, in general. YOu do not specify your PAP anywhere, but your driller should know.
The closer to the PAP & the VAL, the earlier the ball's reaction will be. If it's above the level of the PAP by enough, you should still get decent length and the pearl cover will help on that account also. Just be careful how far "out" yo ugo. It can screw up the ball's reaction and the track, etc.
Unless you want a control drill, I would put the pin any closer than 3" to your PAP.
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"...for advice is a dangerous gift, even from the wise to the wise...."
J. R. R. Tolkien