Coolant in oil/oil in coolant!!!

Got my Blackstone report back and it said positive for antifreeze in the oil. Yes I have used the archoil additives and my understanding is this can give a false reading. So with only 1500 miles on the current oil change I came home and did a complete oil change including a new bypass filter. Took another sample and waiting on the results now. I also change my coolant filter and there is a ever so slight residue of oil across the top of the coolant that was drained from the old filter.
Just did a complete head job late in 15, and put a new cooler in early 15. We went with aged arp studs with oem gaskets and ucf oringed heads. What are the chances this is a cracked block/cracked heads or an oil cooler?
If I have to bite the bullet and do an oil cooler, I'm replacing it with one of BPD units and not have to worry about it again.
Need some guidance here, do I need to look for another motor or oil cooler?
Thanks

Chances are the oil cooler failed. Oil in the coolant happens due to the higher oil pressure while running, and coolant in tye oil from higher coolant pressure when shut off. You may also want to pull your water pump and check for cavitation of the front cover as well. Its not as common as on a 6.4, but ive seen a coiple. If its bad enough it will also do this, as the water pump housing sits right in front of the cam.

I hope your right 6.0 Tech, the truck will sit for now and I'll order the BPD kit while I'm at work and install it during my next trip home. While I have it down I'll check the water pump housing for cavitation, whould have never thought about that one. I would just find it hard to believe the block would be cracked or bad heads.