Will this interfere with the factory trunk seal or bumper alignment?

This lip is engineered for factory mounting points on the E30 platform. Before installation, verify clearance between the lip edge and any existing bumper components. If your bumper has been previously modified or replaced, test fit the lip first to confirm proper alignment.

Should I use adhesive or drill through the existing mounting holes?

This lip is designed around factory mounting locations. Drilling through OEM holes is the standard approach for secure, long-term installation. Apply thread-locking compound to fasteners to prevent vibration loosening. For adhesive-only applications, consult your vehicle's service manual to confirm the mounting surface can support adhesive alone.

How will this perform at highway speeds?

The single-piece FRP construction provides stable airflow management at speed when properly secured. Ensure all mounting fasteners are tight before highway driving. If you experience any movement or vibration, re-check fastener torque values—a loose lip will flex and may separate from the bumper under high-speed conditions.