Modifying Heater Controls?

[TobyArnot]

During the process of some "winterizing", I had a curious thought. On my '70 (Deluxe Heater), the bottom cable operates the damper inside the heater box to divert air to pass or bypass the heater core. What if that damper was blocked closed and all the air was sent thru the heater core. Then use a longer cable to reach thru the firewall to a cable operated universal heater control valve. This would then allow you to regulate the core water temperature - "a real warm" and also completely shut-off flow during the summer.
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Is this workable??