Will this interfere with my trunk when fully loaded?

The rear lip profile is designed to sit flush with the OEM bumper line. Verify clearance by opening your trunk with the vehicle at rest and noting the lip height relative to cargo area depth. Most standard loads will not contact the diffuser.

Should I use adhesive or drill through the mounting points?

This depends on your OEM bumper's existing structure and your desired permanence. Adhesive-only installation allows future removal without fastener holes; drilling provides maximum security. Sand and dry-fit both diffuser sections first to confirm fitment before committing to your installation method.

Will the rear lip stay stable at highway speeds?

FRP construction is rigid and designed to maintain position under normal driving conditions. Once installed with your chosen fastening method and allowed to cure fully, the diffuser will remain fixed. Ensure all mounting points are secure and the surface is properly prepped before finishing to guarantee long-term stability.