I've been slowly but surely learning how to pull the engine apart. Got the block halves apart this evening - that was actually quite a bit easier than I expected. I haven't pulled the rods off the crank to look at their bearings yet, but I already found a rather obvious gouge in the front side of the thrust bearing.
I would say the rest of the main bearings look just fine, although I'm far from an expert on such things. They all feel smooth, no visible or tactile grooves, they've got uniform color (no spots worn through).