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Good end-cap screen:
Ordered 12 from Amazon
Ordered more fast-response thermistors, 150K room temp, Digikey 235-1625-ND
Use Sparkfun-ordered TMP36 analog temperature sensors. They need 2.7 to 5.5V. Provides 750 mV at 25C with dV/dT=10 mV/C.
We want no more than 1V across two-thermistor voltage divider. Mouser sells good part from Analog Devices: 