Interesting thread. I also have a 62 “406” Block and if you are looking for 3/4 grooved bearings, you'll find they are only available in .010 under and I have a steel crank $$ that might need just a polishing rather than going the full .010.
Here are the OEM dimensions for Block and Crank thrust face Dia. also the distance between the flanges at the block.
Cylinder "Block" thrust face b/p dimensions -
1963 and earlier = 3.760" - 3.720"
1964 and later = 4.020" - 3.980"
.07" x 45 deg corner breaks
Surfaces parallel to each other and square with main bearing bore axis within .003 T.I.R.
.915" - .913" face thickness
The later 427 "Crank" Thrust Bearing Flange OD is 3.824" - 3.764".
I believe all FE thrust bearing available today are made to the old style Dia. that way they can cover all with less inventory, but I would check just to be sure
Also I've never had a problem with thrust bearings and that is with a 4 speed and a long style Zoom clutch that was really heavy on the left leg, and that was my everyday street car. .....Hope this helps