cleaning up the slant six head

So heres a kind of dumb question, when porting the intake, how do you get all the way up the #1 and 6 runners?
Heres an even more novice question, why mention porting the intake?

I did not realize that porting the intakes on these engines was an option. I do know on conventional V-8 intakes it is common.

I am under the impression at this point that porting the intake on these engines is not really an option other than to possibly open it enough to match the adjoining head port and then only blending back the cuts so that there are no hard transitions where fuel could become trapped and air may be slowed down ect ect.