"I know another way that the crack repairs where once done, not sure what it was called, maybe it was stitching?
The weld must be made in very short beads, cooling between each bead and peening. Doug Jim, I used to weld quite a few cracked engine blocks, mostly for oval track guys who always forget to drain the water from their engines before freeze up.
One of the cheap buggers didn't like how much I charged so he used JB weld on the block.
Said he drilled the ends of the crack and actually pried the crack apart a bit to force more epoxy in there.
Just V-groove the crack, fill, and let sit 24 hours.
Then smooth surface and no one will ever know it was ever cracked.