Check to make sure that the peghead is not too thick to accommodate the tuners. You can measure or just hold the tuner up to the thick side of the peghead. If it looks as though the tuners will not be tall enough for the bushing bolt and washer to get on the shaft by a few turns, the peghead will have to be trimmed a little thinner. There are several ways to accomplish this task. The job can be done by hand with a rasp. It can also be done using a fence on the bandsaw. A power sander may also be used. Take care not to get the peghead too thin.
Drilling the Peghead Holes
The peghead holes are where the tuners will mount to the peghead. They should be of the proper diameter to hold the tuner shafts without wiggling. Measure carefully and select a drill bit of the correct size. A brad point drill bit can be very helpful in getting the location accurate. Do a test hole on some scrap wood. It is also good to have some kind of backing behind the workpiece to minimize tear-out as the drill bit exits through the other side of the peghead. The tuner holes will be drilled at 90 degrees to the plane of the peghead. The tuner shaft should be snug but not tight. If you have to struggle to get the tuner into the hole, the hole is too small. If the tuner is a little loose in the hole that is okay, but not very loose, a snug fit is best. Experiment with different size bits until you find one that is just right.
Holding the neck in place while drilling the tuner holes can be tough, but is essential. It is fine to drill the tuner holes from either side of the peghead, but be sure to use some kind of backing material to minimize tear out. If it seems like holding the neck still while drilling will be an issue for you, try building a jig to hold the neck in position.
Sanding the Contours of the Peghead
Another cradle type jig such as the one used for cutting out the front profile of the neck can be used for this operation, or possibly the same jig that was used to cut out the peghead profile. As with the bandsaw, the jig allows for steady holding and keeps the angles consistent. Mac uses a small sanding drum chucked into the drill press to sand the curved areas.