Thanks for the encouragement.
I took a close look at the EGR valve on my V6 Explorer. It's connected to the exhaust manifold by a tube with a 1-1/16 nut at the valve. The valve is connect to the air intake manifold with two 10mm bolts.
I do not have a 1-1/16 combination wrench; going to my local hardware store tomorrow (22 mile round trip) to get one.
I can get a 10mm socket and ratchet on the two 10mm bolts, although the one on the driver's side is a sonofabitch to get to. Using a breaker bar and 10mm socket I loosened the 10mm bolt on the passenger side, sprayed it with PB Blaster; sprayed the 1-1/16 nut and both 10mm bolts with PB; left the hood up. Will order the EGR valve today and apply more PB Blaster a couple of times every day until the new one arrives then tackle the job.