You can make a Zbend wire go through a servo arm with a slop free fit. Take a length of that same wire and sharpen one end. Heat it with a cigarette lighter and push it through your favorite servo arm hole.
Work the Z bend through the hole it don't forget to place a drop of oil on the tight fitting joint.
You can also use $20 calipers and a $10 Harbor Freight numbered drill index to correctly size and make perfect sized holes anywhere else on your model.