The adapter is .580 thick. The distance from block to face of crank is .600. The distance from mid plate to face of adapter is .410 with converter bottomed in pump. ATI wants .125 clearance for converter .410 less .125 is .285. , .600 less .285 is .315 that's how much too thick the adapter is. It will require milling .315 off face and boring .315 deeper to center on crank. I was hoping someone knew of a .250 thick adapter that would work with the ATI flywheel. I can cut the ATI adapter down and make it work if I have to, but would rather not.