What was found
WHILE ACCESSING FOR BS 794, FRAME REMOVAL FOUND AFT PIT CUTOUT LOWER BEAM SILL UPPER STRAP HAS CORROSION ON LOWER SIDE. ACFT GROUNDED. REMOVED DAMAGE, FOUND TO BE OUT OF LIMITS, LOCATED AND DRILLED NEW UPPER STRAP IAW SRM 51-40-05-0G-0 TO BE INSTALLED ON MIG 5, OK 5590, W 1.5, O .100, R .082, L 10, D .018.