I also spent some time on my imitation dremel, fitted to the genuine dremel router attachment while cleaning up the neck pocket. I have the bottom leveled nicely, but the sides are just a fraction too tight to accept the neck just yet. I need to take this very carefully, as I don't want to go too far.
A flat, square, sturdy piece of hardwood with some self stick 60 or 80 grit wrapped around the corner may be useful here to tidy and do fine adjustment at the corners Z.
FrankenLab Hand crafting guitars, because Death Rays are expensive.