Ok I've started to remove that dash pad , you'll need to pull the felt backing away to expose 6 screws, after you remove the glovebox itself
there is also an electrical box that you need to remove to access one of the screws RHS
. A minimax 1/4 drive set is ideal as is a stubbie rachett screwdriver. All out ready to cut.
Ok Mudski where you have a bracket my model had junction boxes on it.
Going to cut now, were they your final measurements.
@ cuppa I've taken a pic of your hole {lol} will use as a guide,
here goes