The 8x8 wheeled amphibious armoured personnel carrier provided by the Sri Lanka Armoured Corps replaced which two vehicles
Sri Lanka Armoured Corps: The Sri Lanka Armoured Corps (SLAC) provides the armour capability of the Sri Lanka Army, with vehicles such as the T-55, T-55AM2, and Type 69 main battle tanks, the BMP infantry fighting vehicle and the BTR-80, and WZ551 armoured personnel carriers. BTR-80:  It was adopted in 1986 and replaced the previous vehicles, the BTR-60 and BTR-70, in the Soviet Army.
BTR-60 and BTR-70