The 340 is out....again.....

So, it appears we have diagnosed and identified the problem.
The camshaft bearings which were used were too narrow for the application in my 340.
They are 1/4 inch smaller/narrower than the ones which should have gone into the build.
Instead of riding on the layer of oil, the camshaft as it spun dug down into them because there wasn't enough metal on the bearing surface to hold the oil and create a protective layer; instead the oil ran off both sides of the bearing surface instead because each bearing wasn't wide enough.
The shop has ordered the correct wider bearings and we will see how this rebuild goes.
I found out about this yesterday, and the answer came after consultation with a number of people and entities, including Hughes Engine and Comp Cams. Enough people were contacted and the issue described to where someone was found who had seen this before and was able to comment on it.