here is my solution I have used on many street rods with aftermarket air. Put a 4 port heater control valve in line. This allows water to still circulate in the engine but keeps the hot water out of the heater core. Run a vacuum line and tee into the recirculate door, when you put on max a/cut will shut off the water to the core.
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https://www.amazon.com/dp/B07CV9ST77/?tag=wranglerorg-20