What was found
VTK MSG ON F/O'S ND ON SHORT FINAL. LNAV/VNAV GUIDANCE DISENGAGED. GROUNDED - YES. FMCS BITE PER B737-800 FIM 34-61 TASK 801 SHOWED FAULT LOGGED ON FMC-R FOR LEG 1 - "FMC-R WATCHDOG TIMER" AND FAULTS LOGGED ON FMC-L FOR SAME LEG - "FMC-R RESYNC" AND FMC-R DATE RATE", BUT NEITHER FMC SHOWED ANY CURRENT FAULTS. DUE TO HISTORY, WITH MULTIPLE REPLACEMENTS OF FMC-R, REMOVED AND REPLACED FMC-L COMPUTER PER B737-800 MM 34-61-02-000-801 / MM 34-61-02-400-801. FOUR MIG-51A TAGS INSTALLED AND REMOVED. LOADED FMC OPS SOFTWARE 559775-001 PER MM 34-61-00-470-805 AND CROSS-LOADED OPC SOFTWARE BCG-01T-62, MEDB BCG-01T-A0, LDDB 557362-004, ADDB ASA1007A, AND CURRENT NAV DATABASE PER MM 34-61-00-470-806.