As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE BS 1342, LBL 30 CHORD WAS FOUND SEVERELY RUSTED. THE DEFECT WAS DISCOVERED DURING A RE-ENGINING MODIFICATION. THIS CONDITION HAS BEEN FOUND ON ALL 38 A/C MODIFIED THUS FAR. THE CONDITION IS PROBABLY CAUSED BY DISSIMILAR METAL AND LACK OF DRAINAGE. NOTE: THE RUST CANNOT BE SEEN WITHOUT REMOVING THE PART, SO IT MAY NEED AN X-RAY INSPECTION TO FIND.