First we must gauge how much to cut off each end to make the sides, with all their curve fit perfectly. in this photo the upper end has been trimmed and the pencil marks the cut off point for this side.
Here is how I trim the ends to fit.
Once both sides are trimmed properly they are taped together at the butt-
Glue is applied to the block
And to the bottom edge of the sides.
the sides are slipped into the neck slots, the rear joint is centered on the butt block and clamped tightly to the butt block. Now, side adjustments are made and the sides are clamped tightly to the top.