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Repaired temp compensating board[200/86] posted by Don Foster on
Sunday, 22 October 2000, at 10:25 a.m.
After driving for 3 months with a dead temp gauge, I finally dived into the compensating board.
Yes, I first checked the other stuff—thermostat, voltage regulator, sensor, wiring, connections, and even the gauge. All were OK.
I replaced the LM2902 quad op amp and the PNP transistor on the comp board, and —— temp gauge back to normal! I don't know which of the two was at fault, but since I have a supply of each part, I didn't care to spend the effort debugging to the actual part. In goes the new, out goes the old.
--Sunday, 12 November 2000, at 1:19 p.m.
I replaced the PNP with radio shack catalog part # 276-2023, the MPS2907 transistor. They did not stock the "LM2902 quad op amp" but they have it in the catalog. I decided to try by just replacing the PNP and it worked!
Don Foster sent me this diagram which may help you figure out the lead placement when soldering: 
Thanks for the help Don.
I think this is one of the coolest things I've learned on this site. The PNP is $.65, while the compensator board is over $50 I'm told.
/Jarrod
P.S. While at radio shack ask for the cue cat. Beware of Cue Cat's privacy issues. Regardless, it's a free bar code scanner which may be useful. For example, I hear some guy made a book ISBN scanner.