I examined how the "Priority Main Oiling" works on these blocks.
It is similar to the factory Chrysler blocks, except the lifter bores are bushed (with a 0.035" hole to each lifter).
The oil flows from the oil pump across the front of the block to the right side lifter gallery.
Then it flows to the rear and the oil crossover to the left side lifter gallery is different. The factory blocks have the top/rear external oil taps at an angle to the other lifter gallery. These BMP/World blocks have the top/rear holes going straight down (vertical), and a new crossover passage is cast/drilled from the left side horizontally to connect the vertical passages. See my green lines.

I did put a piece of wire from the #5 main to the right side oil gallery (angled blue line), and that same hole in the main saddle has another drilled hole vertically (yellow line) up to oil the cam bearing.

NOTE: You can see it has both transmission bolt patterns; BB Chrysler and GM. But I don't know how you would mount a starter with the stock factory GM transmission.