360 magnum. 1 piston lower in cylinder??

I saw that. Just wondering how the engine held up over time. From what I have been able to find for the 5.9 Magnums STD bore is...

Stock: 470 +154 = 624 or 469 + 136 =604
ICON IC741: 530 + 118 = 648
KB107: 524 + 132 = 656

Any idea what is acceptable without balance? +/- 10%?