I agree with the above about NOT cutting those heads! I also have a 1966 side-oiler and it makes me cringe thinking about cutting into those heads!
Why not keep those heads the way they are (maybe even sell them for a buck or two) and pick up a pair of Ebrock bare bone heads and have the valve stuff custom done. Mine are massaged to 2.19/1.73 to 2.25/1.75 intake/exhaust.
Heck, if you're dealing with Keith anyway, just pick up a set of his StageII heads and you're good to go!
I also agree with Rick on the previous page about using the BBC rods. I have Eagle H-beam BBC rods and an offset-ground crank that uses BBC journals. -This makes oiling issues non-existent.
-Good luck with your build........that was one heck of a find!