3406e keeps frying one cylinder

We had a truck come in with a 3406e 5ek. Has stage one can from pdi, compound turbo setup and was pushing water out. We pulled head and found it cracked, spacer plate between 5,6 cracked and liner flange on 5 cracked. Replaced all that and the truck seemed fine. Made one run and scored liner 5 and has tons of blowby, not sure why. We put another new genuine cat piston and liner along with 6 new injector because 4 of the old ones didn't pass the test. Makes it two days this time and boom liner 5 again. We did put new oil coolers in after it blew the first time. We pull everything again and take the block out this time and have it checked, it's out of square so we get a good used and have it machines and reassemble everything with all new liners, Pistons bearings and the whole shooting match. Runs for 4 days this time and gets liner 5 again. Did notice a tiny noise from the exhaust at idle kinda like a thumping maybe but not sure, that's before it ate a liner and piston. Everything on this motor is new and its liner 5 every time. What in the world is wrong with this thing and what do I do from here? We tore it down already but I find nothing wrong except the liner and piston. Never got hot, great oil pressure. Is the tune getting one cylinder to hot? Any help is appreciated.

 

That's the only thing I can come up with at this point. Is injector wiring or a tuning issue in the ecm. We are going to take the wiring out of the rocker box while its apart and retune it with a 550 5ek file. Everything else is new in this truck other than wiring and tuning, and it's always cylinder 5

 

All rods are new as well, bought cat cylinder packs with Rods and everything. Bought the cylinder kits found in the 600 horsepower c15. With the slight thump at idle I am thinking it's gotta be something with that injector wiring or the tune.

 

Oh yeah, the take it out back and have a mysterious fire is at the forefront for me I promise.

 

The liner it scored all the way around from the top to the bottom