Do I need to remove the OEM grille before installing this?

Yes. You'll need to remove the factory grille first, then bolt this one into the existing mounting points. It's a straightforward swap with basic hand tools.

Does this come primed or ready to paint?

The grille ships in raw finish. You'll want to clean it and apply primer and paint to match your truck before or after installation, depending on your preference.

Will this fit my Super Duty if I'm running aftermarket bumpers?

This grille mounts to the factory grille opening. If your aftermarket bumper relocates the grille housing, you'll need to verify fit before installation.