If your description is accurate, the temperatures are accurate, it can't be boiling over. It isn't hot enough.
Hot spots in the head are an indication of air in the system.
What water pump are you using? Does it have the bypass hole drilled in it? The Wieand doesn't.
What thermostat is in there? Are you sure it is for the Cleveland and not the Windsor?
Marlin here is really the expert on that subject. Perhaps he will help you with that part?
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