The Art Carr valve required the pump to have an orficed cup plug drove out and the hole tapped for a 5/16-24 set screw to retain the valve and prevent rotation. I converted a pump back to a lock-up by removing the set screw and Art Carr valve from the front pump and installing a stock lock-up valve and spring in its place. Then I drilled a .093" diameter hole completely through the set screw leaving the hex intact. I then installed the set screw back in the tapped hole retaining with red Loctite (make sure you clean the threads with brake cleaner first). DO NOT tighten the set screw all the way down against the newly installed valve, just run it down just under flush and check to make sure the valve move freely with no binding. The set screw will now do the job of the stock orficed cup plug.
You also may need to install one check ball in the valve body side of the seperator plate.
You can leave the encapsulated check ball out of the end input shaft as Bruce (WE4) has told me it will just firm up the lock-up clutch apply.
HTH
Robert