What was found
WHILE A/C WAS IN FOR HEAVY CHECK FWD FUSELAGE AVIONICS COMPARTMENT RACK RT AFT COLUMN, UPPER CORNER AT FR 3. REPLACED AVI RACK AFT COLUMN PN 170-12936-001, IAW SRM 51-41-01, 51-43-01. SEE AAR NRC 4500836-1000-0148 FOR WORK PERFORMED. A/C REMAINS IN YQG FOR COMPLETION.