I will try to update as I go on this intake over the next few weeks to show what goes into full port as cast "598" plus convert to 4500 top.
Top will start out by plugging 4150 holes and drill/tap new 4500 holes next will be some love in the Mill.

The intake runners in the "598" start out small about 1.250" by 1.950" will be about 1.395" by 2.235" when done.