Factory AC Removal Questions

Yes, it's factory.
The underdash part is just the vent, the main AC components are up behind the dash in the AC/heater box.
The vent just attaches to the dash with a few screws, I forget how many- it's been a while since I pulled one off. You should be able to tell once you get down there beneath it.
I'm sure someone will chime in with a little more precise detail.