ok so I had a customer bring in a 2005 lly engine in a 3500 completely stock no mods . they had installed new head gaskets 1 week prior they also had the heads rebuilt and a new turbo it ran for a week and spun all the mains . when i disassembled it there was alot of oil in the radiator . didnt think that much about it because there were a lot of things that were not correctly installed and they did the head gaskets with the engine in the truck . so i started over with a completely different short block used c grade head gaskets and there heads and turbo it has been running about 500 miles now and runs great but still getting oil in overflow tank, no coolant in engine oil. just oil in coolant changed the oil cooler out thinking that might be the prob but not the case . i have bypassed the turbo coolant hoses and let it idle for an hour and no oil there either . i know there is an oil passage in the center of the heads for the rocker shaft but the head would have to be cracked there right ? any other ideas ? thanks