the nut on the truss rod is at the headstock end, under that fancy cocobolo plate (Probably looks lighter because it had recently been sanded). It's not shown in the pictures, but theres just a tiny screw holing that cover on. Any adjustment would be made there. I purposely left the neck a bit chunky because the last thing you would want on a neck-through design would be for it to twist. With heavy strings there's a surprising amount of tension on the neck! And you can't just unbolt it and replace it like cheaper, mass-produced bolt-on guitars. If it ever got really bad, I suppose one would have to remove the fretboard and do some planing, but I'm quite confident it's rock solid.
But ya, if the bug bites again, I'll let you know for sure!