Well
When I rebuilt my continental o300 I ran into this. After several calls to continental, I was told this was pretty much normal(!?!). They did say that if the case was still disassembled, it is possible to “use a countersink to create a larger diameter hole” in the case journal. They also said that if you could see 30% of the case journal hole through the bearing hole, it was ok.
Take it for what it’s worth. I opted to slightly enlarge the holes with a countersink. Engine ran fine and had north of 1000hrs on it when I sold the airplane...