Need advice on 1st engine build - cam bearing damage

You could try and find a talented machinist who could actually fix the cam bores, you could be one of the few lucky ones that it slides right in or you could get mid-evil on it. Like a bunch of people do. Me being one of them. You groove an old cam core lube it up and turn in as it “hones” your beautiful new bearing to the right size. Go slow and back it out and clean out the grooves frequently. Then go into the corner and weep. No sanding! It just embeds the grit into the bearing forever.