Cooling System

Drain coolant.
Use a plier to pinch the hose clip and pull clip away from position.
Disconnect the heater hose by gently twisting and pulling at it till it loosens and comes off.
Heater core connections can break easily so do not use excessive force and if it fails to dislodge, use a sharp blade to cut across the hose seated section to open it up, taking care not to cut into the pipes.

Reverse procedures for installation and fill up coolant.

Run engine with heater turned to maximum with radiator cap off and top up if necessary. Close radiator cap after 5 minutes and run engine to operating temperature. Check for coolant leaks.

Note : It would be necessary to remove other components that are blocking access to the heater hoses.