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I had saw something about that but didn't know the difference. Are they bigger or smaller or just different?
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The difference is that there's a small filler piece on the Aero liners that fills the aero feature at the bottom. The base fenders curve inward at the bottom while the aero fenders stand out in that area. I've also heard that some of the attachment screw holes don't line up, but I can't confirm that. It's a common swap, so there can't be many obstacles. If you do go aero, you'll need the egg crate underneath, plus a few more pieces.