If everything is new, it is highly unlikely that disassembling it will destroy anything. And you will have peace of mind. I had a friend that bought an allegedly rebuilt 383 short block some years back. Wanted me to help him with final assembly and installation. I told him the only way I would have my name associated with that was to disassemble the short block. He balked but when we pulled the pistons and found two that had the ends of the oil ring spacer overlapped....well it was a different story then.