Great write up! I'd been plagued by the insidious "Coolant Sensor Bad" beeping for a couple of years now. I finally had enough, went to Harbor Freight for a $3 solder iron, and yanked my VIC tonight. I wasn't able to identify the bad solder joints by myself, but I merely soldered the points indicated in the photos on this thread. My first solder job was rank amateur at best, but... Now I'm driving beep free, and think I may actually grow fond of the little bugger under the climate controls. Hey, it's an easy way to be sure the oil changes are done promptly.
Thanks a ton, guys.