What was found
MCN - MAJOR REPAIR - DURING C-16 CHECK CORROSION WAS FOUND ON THE UPPER SURFACE OF THE OUTBOARD FORWARD RT AFT LAV FLOOR SUPPORT BS 991, RBL 32, WL 208. MAINTENANCE CLEANED CORROSION AND FOUND MATERIAL LOSS OUT OF LIMITS; REMOVED FLOOR SUPPORT BS 991, RBL 32. FABRICATED A NEW FLOOR SUPPORT AND INSTALLED REPAIR IAW B737-300 SRM 51-40-05, FIG 2-3, PG 4-5, AND SRM 51-40-02, PG 10-11.