I recently replaced the ambient air temperature sensor on my 1999 C5 coupe. It is very easy. The part number is 10248414 (list $11.94). I purchased the part at my local Chevrolet dealer. The part bag was labeled, "Made in China (mainland)". I'm not sure if this part qualifies my Corvette to remain "An American Revolution!"
Raise the right front of the car (use a jack stand......). Remove the black plastic close-out panel under the car on the passenger side. It is attached with 5 or 6 small hex-head screws.
Use a small flat blade to push the "plastic nail" fastener up from underneath the car - the nail holds the sensor to the shroud. The sensor is attached to the right side of the radiator shroud, and protrudes through a small slit in the plastic. It will be obvious when you look at the sensor from underneath. It is difficult to reach inside and pull out the plastic nail connector - easier to push out from underneath.
Reach inside the close-out panel cavity and withdraw the harness that connects to the sensor. Remove the sensor - but examine the connector for corrosion. My original sensor connectors were corroded, but the connector was not (GM sells a replacement pigtail connector for about $32 list). My car is never driven in rain or snow, but the sensor was corroded. I'm not sure why - it has a weatherpack connector.
I used some silicone dielectric grease (GM part #12345579 - small tube and lists for $13.32) inside the sensor before plugging it into the connector - to prevent future corrosion.
Transfer the plastic nail to the new sensor, reach inside the close-out opening and insert the sensor through the hole. Push the plastic nail through the hole and then replace the close out panel.
It sounds complicated - but it isn't and should only take 5-10 minutes to change.
Good luck.