Ok so here's what was done. Removed billet housing from Mancini's and went with good old Ma Mopar oem casting which I should never have doubted. Used standard Fel Pro lip seal and offset it by a couple of degrees, 440 source silicone side seals and gray permatex at all mating surfaces between housing and block.
Thanks for the rundown Matt!
I've seen that 'offset the seals' recommendation before. Do you, or anyone know where that came from? Any factory recommendation to do the off set or just good ol' gearhead ingenuity?