Could you measure those? I am guessing but the first one looks like a high spot was worn off. There still is not a full polish across it surface. The second looks the same. You can see a much better polish on the second bearing now that it has worn. I never worry until I see copper, but....
My worst shells looked very similar to the very last pic, and even that mic'd up at less than 0.01mm of wear. @142k miles
40,000 miles on a car that sees regular high rev action at the ring etc with that amount of wear is a testament to the car i'd think as opposed to be something to worry about.
That is sort of the point that I am getting too. Unless the wear is across the whole surface or down to copper likely it is acceptable and no action need be taken. Assuming the crank has been measured and does not have high spots. The tolerances are so tight it is impossible to get all three surfaces exact so something must be allowed to wear in. Since the bearings are the softest that is what wears. My guess is those marks were mostly there within the first few thousand miles and have not noticeably increased in size.
Glad to hear you are back up and running. Thanks for the update!
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