Randy I forgot I posted this a long time ago, but here is an example of some of the work in the area you were asking about, both the pump and the block.
It will help the oil flow slightly and costs nothing but some time, as long as you have the tools
http://www.moparts.org/Tech/Archive/bb/51.htmlDefinitely have your guy doing the work (or yourself) ream out the passage between the galley and the mains too, to make the passage the same size all the way through it.
A good reamer size to use is in Chuck Senatore's book.
It's probably worth considering reaming the hole to #4 slightly larger than the rest, because the valvetrain robs that journal of oil......I don't know anyone who does that with every build, but it is something to think about....
Really don't think you "have to" do any of this... truthfully you could leave it alone but these kind of detailed changes are nice improvements to make and cheap insurance.
My 400 is tapped to 1/2" NPTF and I did it myself at home, it is not horribly bad to do by hand if a person uses a tapered reamer before tapping the hole. Lacking the tapered reamer, the force required to turn the tap is much higher which creates a greater chance of breaking the iron.
