Yes they seem to be working outside the car using a 100 Ohm resistor and the temp sender w/ heat gun. It was all connected to the car battery so it was all powered up for those tests.
I will say this - the used sender was hard to get a ground connection on. I ended up with an alligator clip positioned so it bit in between the threads. Just sticking it on there wouldn't ground it, and I never got a ground through the hex part of it. Yes I used 60 grit to clean it up but still no ground through that.