I have earlier AD manuals for installing these type of lights that show the measurements, many of the OEM accessories also came with templates. I don't have the later stuff but someone here should. The best way I know to drill metal is to center pop it first, with the measurements or a template you should be ok. My other suggestion is always pilot drill and then go to finish size. As for the A-pillar drilling through it is going to be multiple layers of sheet steel. Good luck!
