What was found
HORIZONTAL STABILIZER BOX STR S-1U AFT HORIZONTAL LEG AT ATTACH POINT TO OTBD SIDE OF RIB 2R IS CORRODED, BLOWN OUT. REPAIRED STR 1 UPPER IN THE RT HORIZONTAL STABILIZER IAW REA B655-62090-MR. CORRODED LEVEL 2, PN: 182T3101-6, STRINGER, EXACT FS/BS LOCATION ON AC: RS STA 2.0 TO RS STA 6.0, EXACT STR/WS LOCATION ON AC: S1R TO S1R. ACFT WAS GROUNDED.