The 360 build that has more turns than Willow Springs

So it was built in 2012-13... How long did it run before it lost the head gasket? Sounds like the heads didn't get torqued properly or those bolts caused issues... One thing when you run ARP or any other premium bolt, they have a higher torque spec, if you use the stock torque spec you never actually properly stretch the fasteners which can lead to a premature failure...

But like I mentioned earlier, pretty common problem on smallblocks...

Blown Head Gasket