My take on the oiling system crossover tube for the small block

If you're not going to restrict the oil going up to the cam bearings I would for sure do the crossover.

What oil pan are you planning to use?

Do not use a grooved camshaft you will partially starve the #2 and #4 mains.

Let's not forget that that camshaft is partially Splash lubricated also.

The passenger side that is the right side the number one passage down to the main you can plug it with a freeze plug up there at the front of the oil galley. That way you don't have to drill and tap a plug into the passage. It's a lot easier just use the freeze plug.