Main bearing priority oiling does nothing if the engine can't get
oil. I almost insist that the road race engines that I do get dry sump systems, or at least wet sumps with big fat Accsumps.
I would personally skip the side oiler block....no use in paying several grand for a 40 year old block when you can get a new aftermarket block for not much more. The 428 block should live if the
oil can get to everywhere it needs to go.