I pulled the heads this morning and the saw a couple things. 7 of 8 pistons were kissed by valves at one time or another.....but anyway, the cooling slots seemed suspect. They look way too small. I started a separate thread about what the slots should look like but I wanted to update this thread with some new info.
1. The pistons are .060 over
2. The heads are 906 heads so they are the heads that came on a 1970 HP block.

For a couple reasons, I've convinced myself that it had to be the head gaskets.
1. I've been through all the normal stuff
2. The upper radiator hose barely has any coolant flow through it; my survivor 69 Charger with completely untouched original 383 has MUCH more pressure/flow in the upper radiator hose.