Cat with diesel in oil

I have a 04 pete with a 475 cat mbn series motor that had a full overhaul about 8000 back. Overhaul was pistons liners rods mains and a cat reman head. Started getting diesel in oil. Ran dye thru fuel system 4 injectors were leaking fuel. Replaced all 6 injectors with cat remans. A couple days later diesel in oil again. Put on new transfer pump. A couple days after this, same problem. Took it to local shop pressure checked entire fuel system couldn't find the cross contamination. The only thing left that i can think of is a bad head from cat. I was just wondering if anyone else had experienced this problem or had any ideas before i take the truck to peterbilt.

 

morehp: after we changed injectors and had fuel in the oil again we ran dye test for a second time and couldnt find the leak. so we changed the transfer pump hoping that was it. but it still is doing it
CbarM: we are checking the injector cups now. if not that then maybe cracked fuel rail in head.
heavyd: After we change the oil after the motor runs for a few hundred miles check the oil and it will be overfull thin and smell like diesel. We have chenged the oil 4 or 5 times in 8000 miles (we changed it each time we thought it was repaired and we had driver change it when he was on road after he noticed fuel back in oil)