Is it worth going to the more robust belleville washer and matching piston used in the later 727 rear clutch drums? Is the earlier, thinner cross sectioned ones problematic? My trans is a '73 so it has the thinner belleville...Im just using a Cheetah reverse pattern valve body so no sky high line presures. 600 hp approx... This is my first transmission job, so im a little in the dark...(pic from another thread on here)