We are pretty sure the heads lifted as there are a few "grey" areas where it looks like gas could have passed. The defined sealing ring has been smudged in a few places.
Also we found some of the studs easier to undo (Still very tight) than others so I feel the studs must have stretched the tinyiest of amounts.
One pic shows an area where you can see the gasket material has been deposited onto the liner and then the water has boiled and corroded right next to it.
We will be using a bigger step, Cosworth gaskets (Not made by cometic) and larger studs to pull it all down! Its a real shame as the engine had run perfectly. Bores, bearing and especially the tappets are in 100% perfect condition!