Editing S130/auto2manualCC php (section)

=== Heater Removal and Modifications ===

The heater unit requires the most modifications in this conversion. All automatic control hardware must be removed, the air-mix door mechanism must be modified, and the heater water cock replaced. Ventilation doors or dampers must also have their vacuum lines rerouted.

Tip:

Removing the dash support bar makes heater unit removal much easier. This bar sits directly in front of the heater, A/C evaporator, and blower.

* Unbolt the dash support bar from both ends and the steering column from the bar. Leave one bolt on the right end to control the drop.
* Drop the bar from the right, lift the left, and remove from the car, noting removal sequence.
* Unbolt and remove defrost ducts beneath the windshield, labeling left/right.
* Drain coolant system. Loosen heater hose clamps between the heater unit and A/C evaporator. Tip: Cut hoses just outside the firewall for easier removal.
* Disconnect the two vacuum hoses from the firewall and two from the inlet damper at the blower top. Save all old plastic connectors, especially “T” connectors.
* Unbolt heater unit: two bolts at the firewall, two at the transmission tunnel.
* Disconnect and label wiring harnesses.
* Pull heater unit away from the firewall, feeding hoses through.
* Remove auto blower control unit from the right side (parts 9–11, Fig. 4-1).
* Remove the entire control unit from the heater front (parts 12–16, Fig. 4-1). Save vacuum hoses and fittings.
* Install the manual control unit (see Fig. 5.3-1 for placement).