Stargrove
Banded Mongoose
Is there a spreadsheet somewhere with the Archangel already built out?It says turret, not turret x2. The x2 is after the installed weapons.
The design sheet for the Archangel is one turret, and that is why the spreadsheet reported the damage as a linked system... because it IS a linked system in a single turret. The spreadsheet would put Turret x2 and damage as 3DD if it were REALLY 2 turrets. (try it in the spreadsheet and you will see that. Edit: Actually, see below. I did it for you.)
My earlier statement on the pilot and gunner being able to pick a gun was incorrect, because I too was looking at the image... but the art is not reflective of the single turret as it was designated in the vehicle design spreadsheet for that vehicle.
I see what you showed in the attached image as "Turret x2 (Pulse Laser Gun (heavy) [F6], dorsal, improved fire control)" and still interpret is as being two turrets with each with one Pulse Laser Gun.
If I do this:

This is the result:

The first entry is what the book shows for the Archangel (makes more sense now) and the second entry is what you showed as an example which I interpreted correctly as two turrets.