I know that 180 won't hurt anything, but she starts running really badly when she gets there. I've had her stall out on me before -- which isn't fun!
I was doing some tree pulling last night and checked the radiator temp with my handy dandy probe thermometer from he kitchen. It showed that the radiator temp was 183°, which suggests to me that the thermostat is working.
It seems to be better when I drive down the road, so maybe I just need to tear down my cooling system and have the components checked out.