John,
here is a pic of the #5 main bearing saddle. The green arrow is pointing to the pink line. The pink line is the area of the upper main bearing shell that is to be chamfered a small amount to allow for some helpful direct oiling of the rear thrust surface and bearing flange surfaces.

This pic does not show the bearing shell in place. The purpose of this pic is to show where the chamfer is to be done. And remember, it is only a small chamfer: no more than 0.040in wide.