Do you mean the rectangular hole that is underneath the base of 'B' pillar? If so I think if you have a look you will find that it is already there.
As for the cut-out in the face inside the vehicle I would suggest purchasing the necessary plastic bits and mark out the hole using them as a guide. I've never done the job mind so that is only my thoughts. The punch that you have quoted needs access from both sides to fit it together before you start to screw it up and may not be too successful on a non-flat surface.
Good luck, keep us informed of your progress.
Rod
As for the cut-out in the face inside the vehicle I would suggest purchasing the necessary plastic bits and mark out the hole using them as a guide. I've never done the job mind so that is only my thoughts. The punch that you have quoted needs access from both sides to fit it together before you start to screw it up and may not be too successful on a non-flat surface.
Good luck, keep us informed of your progress.
Rod