Have any of you tested the ECT sensor/sender resistance at different temperatures, per the FAQ?

Am putting the head back on my 1991 Turbo 745. Could not locate the original ECT and temp gauge sensors - don't remember where I put them when I took them off back in mid-July.

I do have another pair, from an old head I bought from a pick-n'-pull, and I tested the ECT sensor per the FAQ. Below are the readings the FAQ says I should get, and the ones that I actually got at three different temperatures:

FAQ says 1300 ohms at 40 deg. C, my sensor gave 1240 and 1165. Both are too low (computers would think the engine is hotter than it really is), one side of the sensor is within 10%, the other is just barely over 10% off.

FAQ says 600 ohms at 60 deg. C, my sensor gave 716 and 674. Both are high (computers will think the engine is colder than it really is), approx. 12% and 19%.

FAQ says 300 ohms at 80 deg. C, my sensor gave 369 and 360. Both are too high, 23% and 20%. Again, the computers will think the engine is colder than it really is.

Do any of you think that these sensors will work properly? I am leaning toward just replacing them with new ones, but am concerned that the new ones might be just as far off. Any experience with this stuff guys?
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1955 Human, Scott; 1991 745 Turbo, Brunhilde; 1990 745GL, Snuggle Bunny