This is another part of the construction that I have been very nervous about. Mistakes here will effect the final sound and setup of the guitar, not to mention waste all the time spent so far. I watched videos several times, made test cuts, and finally did it. It wasn’t as easy as I had hoped, but turned out ok. The body was routed first, then the neck was routed to the same length tenon as the mortise. There was some additional sanding and chisel work needed for final fit.