This is the head seen in the undesired result sequence. I cleaned the surface up with a wire wheel in order to look at the aluminum deck. This head is from a 90 745T. It had about 190K miles on it.

If you look closely, you can see the upside down "020" stamped above #1 cylinder. It had been surfaced 0.020in about 10,000 miles priorly, as a result of an overheating problem [category of that failure unknown]. And it failed again: the head is warped [again] about 0.012in lengthwise.

WHY??

The head gasket failed and the engine overheated because that prior repair was not done properly. It was done in a half-a$$ed manner.