Will this interfere with my trunk or hood when closed?

No. The Narita lip is designed with minimal downward extension to maintain factory clearances. Your trunk and hood will close normally without any contact or binding.

Can I use adhesive to install this, or do I need to drill?

This lip is designed to use factory mounting points, which means bolted installation. Adhesive-only mounting is not recommended for front lips due to road vibration and wind load. Stick with the standard fastened approach for reliable hold.

How should I prep the FRP before painting?

Sand the entire surface with appropriate grit to promote paint adhesion, then wipe clean. Apply your chosen primer and topcoat per the paint manufacturer's instructions. The Raw FRP finish gives you a clean base to work with.