As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MCN - DURING C19 DISCOVERED CORROSION ON FLOOR SUPPORT AT BS 961, BL 10R TO BL 17R AND WL 208. CORROSION WAS FOUND TO BE OUT OF LIMITS IAW BOEING 737-300 SRM 53-60-51-1A1 FIG 101. MAINTENANCE REMOVED AND INSTALLED NEW FLOOR SUPPORT AT BS 961, BL 10R TO 17R AND WL 208 IAW BOEING 737-300 SRM 51-40-02-0G FIG 12.