Will this interfere with the trunk seal or weatherstripping?

The Aiming profile is designed to sit cleanly below the factory bumper line without obstruction. Verify clearance on your vehicle before final installation, as aftermarket bumpers or prior modifications may affect fit.

Does the FRP hold up to road salt and UV exposure?

FRP resists UV degradation and won't corrode like metal. A quality topcoat (paint and clear) protects the surface; wash regularly in winter climates to prevent salt accumulation in seams.

What's the best way to prep and paint this for long-term durability?

Sand the surface with appropriate grit, wipe clean, and apply your choice of automotive primer and paint. A UV-protective clear coat extends the finish life significantly, especially for dark colors.