Engine top and bottom are off.
The head and oil pan were pulled this evening. Diagnosis confirmed, no surprise there. Counting stopped at 58 bits and pieces of connecting rod, but at least it had the courtesy to remove itself from the crankshaft thus saving some effort. The straightest line crack was across the oil hole, I suppose no surprise there either. The piston is marked STD. There is some scoring at the top of the piston in the vicinity of the valves, presumably from rubbing against carbon deposits? The top ring was split in two, it's interesting how the width of the ring is not uniform; presumably this has been split for some time. The cylinder bore did not leave me choked-up; no sign of scratching or anything else of note to the eye.
This is to be classed as a field repair, so avoiding mission creep will be key. 16-G gets the full rebuild this year!
Sorry I don't know how to get the pictures into the text yet, but they are attached.