Are they #2/4 ? If so the oil is not turning to the bearing from the main oil gallery ,oil speed is too fast.You would be turning it to many rpm and should do the oil mods to block ,but if all bearings look like that its wore out.
Check your timming at 3000 and 5000rpm you could have too much timming a lot of people never check it at top speed and have seen many engines break timming chains and destroy the top end when the exhaust valves sizes in the guide from donations in circle track engines
I had a machine shop cut a small grouve in the 2/4 cam journals on circle track engines I ran ,then you can restrict oil coming thru the head under the shaft if needed ,this is the only way you can save some cheap roller rockers bushing wear when using hydraulic lifters.