Shrinkwrap bones are clapping my booty cheeks

I thought I had ascended to rigging god status when I figured out this set-up for an oval eye that slides on the surface of this characters head but it was all a lie.
EyeDemo

when the neck turns in the Y axis all hell breaks loose.


How can I keep my shrinkwrap bones in alignment with each other and also have it not break when the neck rotates in the Y axis?

currently I achieve alignment with a copy location X-axis however this appears to break my eye rig when the neck rotates.

Any advice would be super cool.

Try using Local Space.