Ok I’ve tried two of those Mancini billet seals on my last two biulds. Both came in as leakers. One Still leaks but the other is sealed fine. My guy that does my machine works has a 440 builds that has been through several seals with the stock retainer and they still leak. These things are hit or miss seams like on B.B. Mopar. My question is will the factory rope seal work better and can you still get them? I remember always having oil leaks back in the day and it was just something you lived with.