Yes, the temp needle was erratic. My guess is that the thermsotat is stuck open as it takes forever to come up to temp.
The 4 oxygen sensors were the main reason I was hesitatnt to swap them out. They aren't cheap either. I'll swap the thermostat this weekend and cross my fingers that the light goes out. I would assume it will go out, although I hear ocassionally you need a reset switch to do it.
One more thing: the factory manual says I need this set of tools to secure and remove the fan:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2493861103
Is the job easy to do without them or should I just bite the bullet and buy them?