Just like when you drill to tube a lifter galley you probably could of drilled and tapped and ran two big plugs back to back in the front for your fix or part of it.

BUT many will agree that a small block mopar really needs little oil mods to live, I run over 13:1 on spray and at times 7600 rpm shift points with next to no mods.

If you look at an X or R block the areas your trying to hog out are only just marginally bigger then a early 70s block and they run dirt/oval track at 8k.

I think your trying to hard. But props for trying.