Need big block help

I usually end up around 35* on street/strip BBM.

As for the seal, they all take a 2 piece.
However there is a one piece available.
I think it’s from “Fastfish”.
I believe you have to slit it for the install.

I only personally know of one installation of one of those, which was fine at first, then failed miserably after about a year.
It basically just “disintegrated” and oil was just running right out.