We created a toe stick that has custom ends for different wheels to index the wheel instead of trying to balance a flat surface on a small area.
This particular one is for the 15" Rays wheels used in Spec Miata. The ends of the tie stick at contoured to fit inside the wheel lip as well as being contoured to the outside diameter of the wheel, so basically it centers itself at the centerline of the hub.
The ends of the toe stick index the inner contour of the wheel leaving the outside lip which often gets beat up out of the equation for continued accuracy.
