This hole needs a perpendicular hole for the up haul line. It will go through the perpendicular hole, then be tied off.
|Centerboard orginal holes|
In the photo below, you can see that I've filled it with epoxy filled with micro balloons and a bit of colloidal silica.
They will be drilled back out larger.
|Hole filled with epoxy|
|The other holes filled with epoxy.|