They can be very tight. I've used a tubing wrench. The flat 6 sides work well. In the yards a vise grip works. Before you go to the trouble of removing it, do the troubleshooting using a hand vacuume pump to open the egr with the engine at idle.
1990 to 2005 used one in good condition. Stay away from the 2.5 DOHC. Lots of good rust free ones in CO.
Lot's of used cars are way overpriced now. Have to watch and be ready to jump on good ones.
Problem is most folks don't load the circuit. They unplug the connector... read voltage and buy the part thinking it's failed. $80 may be a bit but it's cheaper than a lot of parts.
If it saves you one time, most likely you've paid for it.