As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CYLINDER OVERHAUL, FOUND LOWER PORTION OF THE EXHAUST GUIDE WAS MISSING APPROXIMATELY ONE-HALF OF ITS MATERIAL. THE UPPER PORTION OF THE GUIDE THAT PROJECTS IN THE ROCKER BOX AREA WAS FOUND BROKEN OFF LEVEL WITH THE CYLINDER HEAD.