What was found
NR 1 ATT ON PFD FROZEN, NR 1 FD FAILED, NR 1 A/P & NR 1 YAW DAMPER TRIPPED. SUSPECT NR 1 ADC FAILED. ON SHUTDOWN IRS MONITOR SHOWED NR 1 IRU, FOR DRIFT & GS. REMOVED AND REPLACED NR 1 ADC IAW MM 34-11-34-4. TESTED PER 34-10-00 P BLOCK 501. REMOVED AND REPLACED NR 1 IRU IAW MM 34-25-34-4. TESTED PER 34-25-34-5. AFS & LAND TEST PERFORMED PER MM 22-40-00-5. R/I FROM FACT PREMATURE REMOVAL/INSTALLATION OFF MFG 461600-0800-0801, POS 1 SRL 0033, TAG 998311.