Will this interfere with my front bumper undertray or splash guard?

The lip mounts to the bumper beam itself at the factory anchor points. If your undertray or splash guard sits low or extends forward, verify clearance before finalizing installation. Minor trimming of existing plastic undertray edges is sometimes necessary to avoid contact.

What's the best way to prepare this for paint?

Sand the surface to create tooth for primer adhesion, then apply your chosen primer and topcoat system. FRP surfaces benefit from proper surface prep — wipe down with a tack cloth before each coat to ensure a clean, smooth finish.

Does this require adhesive, drilling, or bolts to the bumper?

This lip uses the factory mounting points on the OEM bumper — no adhesive required. Verify bolt hole alignment on your bumper before assembly. Hardware is not included; source fasteners compatible with your OEM bumper beam diameter and thread pitch.