Did exactly what that person stated on 460ford.com said to do, after he pulled his engine 6 times to repair his
oil leak. I put about a .012 crush when I bolted up the rear main cap and didn't use RTV on the seal mating sufaces, also trimmed off the tabs because when you seat the seal in the grooves the lip of the seal will have a flat spot in it. Then ran the engine for about 2 hours on the test stand, not even a seep. Don't worry about that seal spinning in the groove, if that happens you have bigger problems then seal spin. I did mic the crank grooves, 1970 dove 4 bolt, D9T, Scat crank and stock crank came up with different measurements.
Bottom line---you have to machine that rear two peice main seal accordingly.