1970 Chevy Monte Carlo heater core

REMOVAL:
Disconnect the negative battery cable, then drain the engine cooling system to a level below heater core.
Disconnect and plug the heater hoses at the core tubes. Plugging the hoses will help prevent excessive coolant leakage.
Remove the module's rubber seal and screen. If necessary, disconnect the washer nozzle from the cowl.
If necessary, remove the right windshield wiper arm.
As applicable, remove or disengage, the diagnostic connector, high blower relay, thermostatic switch, ground strap and/or electrical connectors from the heater core module cover.
Loosen the retainers and remove the module's top cover. The cover is sealed to the module and this seal must be broken before the cover can be removed. Be absolutely sure that all cover fasteners are removed before attempting to break the seal or cover damage will result. Take your time and be careful not to force and crack or otherwise damage the cover.
With the top cover removed, loosen or unclip the core retainer, then carefully lift the core from the vehicle.

INSTALLATION:
Thoroughly clean the mating surfaces of the cover and the module of all old sealer.
Install the heater core to the module and secure the retaining bracket.
Apply a coating of sealant to the cover, then install the cover and tighten the fasteners. If the windshield trim plate was loosened for clearance, reposition and secure it.
Engage the electrical connectors and components to the module cover, as applicable.
If removed, install the right wiper arm.
Install the module screen and rubber seal. If removed, install the washer nozzle to the cowl.
Remove the plugs and reconnect the heater hoses to the core tubes.
Connect the negative battery cable, then properly refill the engine cooling system and check for leaks.

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