My buddy was building motors for Roush nascar motors. He just had two motors wipe out lifters in bbc same way. Parts were from performance products, the parts have been coming from anywhere they can get em. The metal quality is terrible. This COvid bs has caused issues in the parts business. The lifters were soft. Take a good lifter and put it in a vise. Hit bottom with a punch. You will see how soft it is. It’s either that bad of metal or u forced lifters that were oversized (too big) into a block that needed bushed.