That bolt is either overtorqued or undertorqued. Is that bolt also potentially bottoming out into the transmission bellhousing and not really holding the starter tight ? Just a wild guess. Or just a manufacturing defect in the cast itself. And I did notice that bullnose ford in the background ;)
@WorksforMe they were torqued to 24ftlb. It was a casting defect with that lower boss, you could see where there was another crack propagating behind the bolt hole. That was maybe the 10th time I've started the truck since replacing the starter.