Fit the neck block to the head

Not only do the three surfaces of the joint have to meet perfectly, but the way that the head is mounted on the neck has to be monitored. There are five dimensions to be watched; in this picture I am checking the clearance of the neck projection at the scroll. This determines whether the head looks crooked and it also ensures that later on it will be possible to plane the neck surface without accidentally planing the top of the scroll.