First, drain your system's coolant into a container (and dispose of properly)
Locate the two hoses that go into your firewall. These hoses go into and out of the hearer core and remove them. There should also be rubber insulators on the inlet and outlet of the heater core. Unscrew each hose's fastener and remove these hoses. Do not dispose of these hoses as they will be reused.
Next, go iside of your vehcle and remove the under dash cover and then locate the heater duct. It has a number of small screws plus clips that hold it in place, remove them. The duct should then be removed. There is also a small cover over the heater core inlet/outlet pipes. It is held on with three screws, one of which is a little hard to see, remove them and take off the small cover. It may be glued in place by a tar like insulating material. The heater core is held in place by two strap clamps over it which are held on with two screws in each.
Finally, Remove the screws and clamps. The heater core will now come out
Reverse the procedure to install the new heater core. Refill the coolant and check for leaks.
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