I think I have read that you never want to use a threaded female PVC when connecting to metal. It is almost certain to eventually crack and fail. Although now that I think of it that warning was for PVC and cast iron.

"the fitting should be male pvc to female copper,"

Also, if the main was metal and is now PVC, was your elec. ground updated?

Thanks so much for your feedback! Snoonyb, the previous main was an extinct version of plastic--"blue plastic", so I believe we're in good shape electrically, but thanks for thinking of that.