Sometimes I use a waterproof thermometer stuck in the radiator with the car idling--cap off. Use the same kind they stick in the roast beef at Hardees to check the temp. It's not a pressure tested deal, but gets you familiar where the car will operate. Once you establish it's under the boiling point, get one of those auxiliary gauges that's accurate enough to display the temp. If your first test says your under boil and the aux gauge hooked to your sendor says your way high just like your dash--it's probably the sender. If it's different than your dash guage, then you have to figure from there.
Doug
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"I pity the fool that doesn't try my cereal!" Mr T
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