Greetings.
For Some time my 87 245 temp gauge has been acting very strangely. It would approach a "normal" reading and invariably drop down to no reading at all after 5-15 minutes of driving. Next trip, same thing. I checked the sensor, and the under hood wiring. Finally I consulted the Brick Board archives and was directed to the real culprit - the temp compensating unit in the instrument panel.
I removed the compensating unit and cleaned the terminals as per the archives instructions, next I resoldered the board (Thanks Don Foster!) and reinstalled it. Viola! Success! It reads normally again.

My only snag was when I removed the three wire quick disconnect to the speedo. I broke off the retaining teeth on the white plastic u-shaped hold down clip. Luckily I am a professional Model Maker and was able to modify/repair this clip.
If any one else is removing their instrument panel here is my $.02 on how to avoid this. After you remove the 4 screws holding the instrument panel and slide it forward, look behind the unit from the passenger side. The white clip I'm talking about has three wires and is located in the center of the unit. There are two "spikes" that serve as pressure points on the retaing clips on the side of the unit you are looking at. Pull these slightly toward you as you slide the clip itself away from the unit. This should keep you from shearing off the tiny teeth in the retaining clip. After clip is removed, the connector itself slides off easily.
If you do break the clip I repaired mine by fabricating two small styrene strips with oversized teeth on them and glued these piggyback on top of the old arms. Otherwise you could probably slide a piece of cardboard or something between the clip and the "spikes" to provide enough friction to hold the unit in place until you get a replacemnt clip from the dealer.

Anyway thanks to all contributors, especially the venerable Mr. Foster.
Long Live the Brick Board!

Chris