Will this diffuser scrape on steep driveways or parking lot inclines?

Rear diffusers sit lower than the chassis, so scrape risk depends on your vehicle's ride height and approach angle. Measure the rear bumper clearance on your setup before finalizing fitment. If you've lowered the car, test clearance slowly on a known incline first.

Does this 2-piece design require any special alignment during installation?

The two pieces are designed to meet at the diffuser centerline. Ensure both panels are square to the bumper before securing — use a straightedge across the rear bumper width to verify alignment before final fastening.

Can I install this over the factory rear bumper, or do I need to remove the OEM bumper?

Installation method depends on your mounting strategy and whether you're replacing or supplementing the factory diffuser. Examine the factory bumper's mounting points and compare them to the diffuser attachment areas. Some builders modify OEM points; others use the diffuser as a standalone rear panel. Verify clearance and contact points on your specific setup before drilling or permanent fitment.