What was found
AT 200 FT AGL ON LANDING IN SFS, GOT A CABIN SMOKE LVL 3 ALERT, IT WENT OUT SHORTLY. ALERT ON AGAIN DURING LANDING ROLL, THEN OUT. EMERGENCY DECLARED. ON TAXI IN, CABIN SMOKE LEVEL 3 ALERT ON STEADY. APU RUNNING. ENGINE SHUTDOWN. F/O SMELLED SMOKE. EMERGENCY EVACUATION DECLARED. REMOVED AND REPLACED SMOKE CARGO COMPT DETECTOR AFT CARGO DETECTOR 5 PER MM 26-14-01-4, OPS CHECK PER MM 26-14-01-5 PASSED. REMOVED AND REPLACED NR 2 FIREX ENG/APU CONTAINER. REMOVED AND REPLACED MSC, OPS TEST. REMOVED AND REPLACED NR 1, 2 AND 3 WATER SEPARATOR AMM 21-54-05-2. C/W MTSI ITEM NR 3 WRI 26-1/9032 AIR CONDITIONING PACK AND DISTRIBUTION DUCT ODOR CHECK PER MM 21-53-00-7 SATISFACTORY, A/C OK FOR SERVICE.