Neck pocket!
For a template I used three pieces of wood double-stick taped flush with the neck pocket already in the top, then I used chisels and this cute little planer that I hadn't really found a use for until now to clean up the pocket and make it square.
Had never done one before but it turned out as well as I could have hoped. The plan is to do a set neck. Ive got a small, tenths of a mm, gap at the top of the neck pocket between the neck and the wall of the pocket but as the table wood is so dark some wood glue and saw dust should make that pretty invisible... What do I need to know before glueing in the neck?