Thanks to all who replied. I always thought that water shut off valve was called a gate valve because I was always told to shut off the water at the gate in front of the house.
I am not familiar with the copper union fitting and decided not to install one. I don't know if code requires one when connecting to pvc.
I was concerned about damaging the threaded pvc fitting. I cut the pipe above the gate wheel valve and very carefully turned the assembly unscrewing it from the pvc fitting. I cut the 1" copper pipe near the stucco and all the old copper plumbing was now removed.
I first soldered the 1" threaded fitting to copper pipe. I soldered the lower part of the ball joint onto that length of copper pipe. This was done in the garage. I immersed the 1' threaded fitting, pipe, and ball joint in water. When the pieces were cool, I screwed the threaded copper fitting , pipe, and ball joint, into the pvc fitting. I next soldered a 1" couple into the pipe coming out of the wall. From this point on I started connecting pipe and fittings to a configuration I drew on paper. I cut all the pipes very carefully and cleaned every piece with SOS.
Every 90 degree elbow, 1" x 1/2" reducer, 1" tee, couples, 1" pipe, 1/2" pipe, ball joint, and 1/2" male threaded adapter were connected and ready to be soldered. I started at the 1" couple and ended at the 1/2" male threaded adapter. Finally, I screwed the new Arrowhead #253 hose bibb in.
I looked at every soldered connection and was satisfied that they were water tight. I turned the water back on at the curb and checked for leaks. I saw none.
Here are some pictures of the finished job. The work took me about 3 hours from start to finish.