CM870 liner failure

[CornHauler]

I have CM870 in a 2007 Peterbilt that I did an out of frame overhaul on and drove it about 2,000 miles and it locked up. I opened it up and found the #4 liner is all busted up and the piston is in there sideways. The bearing on that cylinder is fine. The pieces of liner that I have looked at don't appear to have any scoring or anything that I can see. This happened at 55 mph driving down the road grossing a 140k. I had the block decked and counter bores cut but only ended up with .0014 instead of .0015 like I wanted. This isn't my first overhaul and I followed the rebuild instructions on quickserve as close as possible. The truck was tuned by Running rough and seemed to run just fine. What am I missing?