Many people don’t realize it, but a pickup won’t sound right unless it’s at the right height. Those screws on the side are there for a reason! If a pickup is too close to the strings, it will be louder, and sound dark and muddy. This may sound like a good thing for some, but it’s really not. Pickup height is measured similar to the way action is:

• Put a steel ruler on top of of the low E string’s pole piece on the neck pickup, and measure the distance between the pole and the bottom of the string. For single coils, this should be 6/64″ (2.3813 mm).
• Do the same for the high E’s pole piece. This should be around 5/64″ (1.9844 mm).
• Repeat for the bridge pickup.
• On humbucker equipped guitars, the pickups are not as close to the strings, since they have higher output. It should be 4/64″ (1.5875 mm) on the bass side, and 3/64″ (1.1906 mm) on the treble.
• Unless you have a guitar with an angled neck, such as most Gibsons, pickup height will be relatively the same. This does not apply to Jaguars unless you have shimmed your neck (I’ll discuss that later). Just remember that the pickup height should always be the same amount from the strings.

This information was taken from Ranger’s Guitars, which seems to be a dying website. This is the reason I re-blogged it to save the information. I liked his breakdown and simplicity of the instructions.