As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MCI -TWO RIVET HEADS POPPED OFF AND INTERGRANNULAR CORROSION UNDER FLOOR MOUNT ANGLE AT STATION 542 LEFT BUTT LINE 37 IN FORWARD CARGO. AREA OF DISCREPANCY IS FOUR INCHES BY FOUR INCHES WITH A DEPTH OF .100. INSTALLED NEW FLOOR MOUNT SUPPORT USING HI-LOKS PER SRM 7 40. SYSTEM GROUND CHECKED NORMAL OPERATION.