Traditionally on f style mandolins, ears are used to make up the full width of the peg head to save having to use an excessively wide piece for the neck. I did this on my mandolin too, even though the peg head is much smaller than an f style peg head.
These are the ears I mentioned earlier being glued to the neck. When they dried, I belt sanded the top and bottom faces smooth, and glued on templates for the neck and peg head profiles . This was again cut out with the bandsaw. I used the piece cut out from the under the neck, while cutting the side profile, to hold the neck's top face parallel to the table of the bandsaw while cutting the top profile.