That does it. I will change the compressor to a rebuilt unit and use the one on the car as a core. It seems the labor to change both expansion valves is more than the price difference between the old compressor and the new. So if there is risk of contamination from the old one, there is no sense in risking that, as well as having to replace it with a new compressor after discovering the old one introduced dirt into the system which is now clean. Sometimes the right way is the least expensive way in the long run.