I will add to this list of suspects. When chasing an overheating issue on a 50's GM car the problem was a radiator cap that would not hold pressure. Cap test kits are available n/c at most national parts stores.
Bob
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From: "David Dumais" To: chrysler-300-club-international@xxxxxxxxxxxxxxxx Cc: Sent: Monday September 29 2025 9:52:53AM Subject: {Chrysler 300} 413 with a/c thermostat