Will this chrome trim scratch or peel if I remove the old grille?

Chrome plating is durable but can be damaged if you pry the old trim off aggressively. Use a plastic trim tool to gently separate it from the mounting points. Take your time and work from multiple angles to avoid gouging the back panel where the new trim will sit.

Do I need to use sealant or adhesive where this bolts on?

These bolt to factory points—adhesive is not necessary. Hand-tighten bolts first to verify alignment, then torque to spec. If there's a gap between the trim and body, check that the old grille sealing surface is clean and flat before final tightening.

Can I polish or refinish this chrome if it gets dull?

Chrome trim can be cleaned with a soft microfiber cloth and chrome cleaner to restore shine. For heavy oxidation, a dedicated chrome polish works well. Avoid abrasive scrubbers or wire brushes, which can scratch the plating. If the chrome flakes or peels, full refinishing would require removal and professional replating.