Thanks guys,
I can't believe this took me hours to do but here is what finally worked. I sprayed it down several times with penetrating oil and used the impact wrench with a pipe wrench on the yoke between doses of penetrating oil. While the impact wrench didn't work, I think it helped to get the penetrating oil to sink in. Finally, I got the pipe wrench on and the handle propped up on a jack stand so it was parallel to the axle. then I got the socket and breaker bar back on and put the handle on a 2-ton floor jack. I practically lifted the truck off the ground before it finally started to give. I finished it off with the impact wrench.
Wow! I had no idea what I was getting into, but I'm glad to have it off. Thank you all for the tips!
