John, the book I keep under my pillow says the bearing bores for the crank and cam are not in perfect alignment so the
oil holes are off center. Don't worry about the off center holes check the size of the opening. A drill bit shank can be used to check the size of the hole.#1 is 17/64, 2 is 9/64, 3 is 9/32, 4 is 5/32, 5 is 9/32. They shouldn't just be opened up as a bigger hole is less restrictive and may cost you in
oil pressure where it's most needed. If you check them to the numbers given and they need opening up I would recommend a straight flute or at least a low helix drill with something that thin and soft. The other thing is to modify a drill point to no rake on the cutting edges. A chamfer tool will deburr the hole effectively after drilling.
Hope this helps
Cheers Nick