CBP generally looks to whether the component forms part of the vehicle's outer shell, passenger compartment, or load-bearing body structure (classifiable here) versus whether it is a mechanical, drivetrain, or suspension component (which would fall under other headings in Chapter 87). Technical drawings, assembly diagrams, and the OEM's parts classification are key supporting documents. When a component serves dual structural and mechanical functions, the essential character or primary function typically governs.

Section 232 tariffs on steel and aluminum derivatives can apply to body stampings that are processed steel or aluminum articles, depending on their form and the country of origin. Whether a specific stamping qualifies as a 'derivative' article subject to Section 232 depends on its HTS classification and the applicable proclamations. Importers should consult a licensed customs broker to assess whether their specific stampings trigger Section 232 liability in addition to the standard Chapter 87 duty.