Jake thats a typo. The correct measurement is 4/32. This is just a guide to go by. The closer you get the magnet to the string the stronger the signal but the shorter the duration of the string vibration. Every set of pickups has their own "Sweet spot" depending on the strength of the magnet and the number of winds in the coil. You may want to start at these measurements and tweak them as your ear tells you what sounds good to you.

+1
Start with the recommendation and adjust according to taste.
Your ears will tell you when it's right.

-T

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-T

"You can't spend what you ain't got, you can't lose what you ain't never had" ~ McKinley Morganfield