The installation and removal of the heater assembly in a pickup are as follows: the heater assembly is removed and then disassembled into five screws to remove the two halves. Unscrew the fan retaining nut, give it a slight tap to loosen the fan, and then take the fan and the nut out of the motor shaft. The second step is to remove the three motor-to-case retaining screws and remove the bullet connector to the resistor and ground screw and then rotate and remove the motor out of the case. To install, put the motor back into the case and rotate it a little, fasten it with the retaining screws and re-connect the bullet connector and ground. Install the fan on the shaft and lock it using the nut, re-fit the halves together and install five retaining wire screws, and re-fit the heater back into the trucks and test its operation. To work on the MPV front, you have to take off the side lower panel of the passenger, the side lower cover, the motor connector wiring, and lift off the blower motor, but the process is inversed to how the process is done. The battery ground should be disconnected on the rear, rear heater temperature control knob to WARM, empty out the engine coolant, remove the driver's seat, and disconnect the heater hoses at the core tubes, disconnect the wiring at the connector, lift out the heater case which has the mounting bolts removed, and then lift out the blower motor, and installation is the reverse of disassembly and replacement of any damaged sealer. In the case of the Navajo which has no air conditioning, the negative battery cable must be disconnected, the air cleaner or air inlet duct must be removed (as needed), the vacuum reservoir must be removed as well as the blower motor and wheel out of the heater blower assembly by removing the screws. Installation To install, fit the blower wheel on the motor shaft, use a hub clamp or push-nut to fix the wheel, attach the blower motor and wheel to the heater blower assembly, re-attach the cooling tube and the cable of the wire harness, re-fix the vacuum reservoir, and lastly re-attach the negative battery cable, checking the system as it works. In the case of the Navajo with air conditioning, disconnect with the negative battery cable, disconnect with the wire harness with the motor, may need to remove the air cleaner or air inlet duct, may need to remove solenoid box cover, disconnect blower motor cooling tube and remove the blower motor and wheel assembly out of the evaporator assembly. The blower motor wheel should be installed on the shaft with a new hub clamp, a new motor mounting seal, the assembly should then be installed in the blower housing and the cooling tube and electrical wire harness reconnected, the solenoid box cover should be restored (where present) and finally the negative battery cable should be reconnected with observing the blower motor operating at all speeds.