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

I don't think anybody has mentioned it but is that little plug that's down there underneath the pressure sending unit approximately 7 and 1/2 in down or about 2 and 1/2 inch up from the bottom of the block missing. You know the one that doesn't affect oil pressure according to many experts.

I'm pulling the motor today. How can I check that? Inserting a rod down that pressure take off port?