If it's not boiling, it's not hot. With a 14 Lb. radiator cap, the coolant can get to 250 degrees + without a boil-over. Use at least a 180 thermostat, and 195 is better. A 350 is designed to run betweeen 200 and 220 degrees in everyday use. Anything above 220 might be a concern, but below that, just drive on!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!