Ok, I finally got back to the motor. There was NO oil in the bottom of the pan, so I took out the thermostat and finished the cam break-in for another 10 minutes. The 190 thermostat WAS opening fine in boiling water as well.

After that I set the initial timing, we shut down the motor and started looking closer for coolant in the motor.

I pulled the PS valve cover and it looked like we had coolant. A camera down into the lifter valley showed what looked like coolant. I pulled the intake and found this. There was actually green coolant in the upper bolt hole for the timing chain cover and a little coolant pooled by the #1 lifters. There is a little pooled between the lifters for #2 and #4 as well.

When I pulled the intake, I saw a little bit of water run down the inside of the block to where coolant is pooled at the #1 lifters.

There was actually some coolant in the upper bolt hole for the timing chain cover. The screwdriver is pointing to the bolt hole.

I have an old Edelbrock intake and the mating surface to the head seems true with a straight edge laid against it. The intake manifold gasket appeared to form a good seal between the head and intake.

I don't know if the heads are cracked or if I'm not getting a good seal at the front of the heads to the intake and it's allowing coolant into the block.

NO white smoke, or any smoke, out of the tail pipes.

Ideas?