GUI flashing on hover

When I hover over an object, a box appears above it showing some data. If the mouse is over the object, the GUI flashes on and off because I'm using OnMouseEnter/Exit to show/hide the GUI.

If I want a data box to appear above a hovered object, and have buttons inside it be clickable, what is the best way to do it? I tried increasing the Y of the BoxCollider so I could move my mouse up without the OnMouseExit triggering, but when the GUI is hovered it acts like an OnMouseExit.

And having a close button isn't possible due to the amount of objects.