I quite enjoy building guitars, however cutting the truss rod slot is a bit of a pain. A plough plane would be ideal for this - I've been bitten somewhat by the plane making bug, so I've been looking around a bit for information online on building one. However I haven't found too much on the topic aside from references to the "Wooden planes and how to make them" book I've had my eye on for a while. Any other suggestions? The concept looks easy enough, but I'm sure theres a bunch of gotchas involved...