I'm with Shadow man; I rarely have the radio on underway.

I would personally prefer a warning light and buzzer; a shutdown could come at a very bad time, where a backing off on throttle or downshift would cool it down quickly.

A low coolant light (mine has one) would let you know that the heat wasn't due to loss of coolant. The voltmeter and P/S response would confirm that it wasn't a broken belt.

The Breakaway that was Dr. Charles and Helen Yale's is on a third engine. To give you an idea of the consequences of failing to monitor engine (albeit 5.9 not 8.2) temperature , here is the essence of the 2008 work order from a Cummins shop:
... lost all coolant. found radiator drain cap and radiator fill neck hanging off radiator by drain hose. solder bead had melted. find overflow tank melted.... remove engine and replace with recon.

Even though you can raise the boiling point to 240 degrees or higher by use of anti-freeze/coolant, i figure that if i hit anything above 210 i am looking at a $10-12,000 rebuild. A few times on hot days, climbing long steep grades, ( like 107 degrees going up the hill from Laughlin, or going up the Grapevine), when my temp has started to climb i have turned my heater on to help shed heat....it might get a little uncomfortable for a few minutes, but better than losing an engine. I have never run with the ac on, we just have a couple of windows open.