That`s a bummer! If it was a big block , I`d say swap out the oil pump with a standard volume/pressure oil pump and see if that doesn`t fix the leak. Since it`s a small block then you have to deal with that angled adapter. I guess once apart it`s just a matter of making sure all the surfaces are clean, flat, and sealed with silicone when you get it back together. You can also use a high flow filter which may actually reduce the pressure at the filter some. Ah, the debugging of a new build.