Today, I decided to cut off the old PVC and replace the whole thing. I should have just replaced the first "T". Then I used slip bushings in my plan, bad idea. William started helping around the big blue shaved down coupling. It did not fit.
I installed the old backflow preventer back on. Then we turned on the water. The water started pulsating very badly. We watched when two "T’s" broke loose and you know the rest of the story. It was late and we were in Wylam so we closed the wash and cut the power to the pumps and ran away.