If I'm reading you correctly are yours hitting on the side edge of the bearing or the angle in the radius of the crank? I've "hand" chamfered my 302 bearings for years to make sure the oil would flow out properly. I have more side clearance than stock so it's always one of my checks and I do it by putting the bearing in the rod and use a bearing "knife" to add more clearance for the oil.(about a 45 degree angle)
The GMC has a lot of bearing surface so this has never been a problem. My side clearance is a minimum of .015"+ The side clearance comes from using a surface grinder at work.
Good Luck
