checking for cracked head or bad head gasket..

whats that hanging below the gasket in pics?

right below where the heat cross over would be, no cross over on theses heads though.

if they cracked in the runner from a thin spot, you'd see a clean area where the crack is surrounded but an tinted/golden .

the cork seals will do nothing for sealing the water cross over.fyi

After 4 tries I would rtv metal plates over all 4 cross overs [like when when you block the exhaust cross over] bolt down the intake snug [no gaskets] and then after the rtv completely dries...pressure test it again and see what happens.
that way the passages are blocked, so if it leaks it'll be from somewhere else.