I don't think replacing the lens is an option. I wet sand mine (2004 TT) with 1500 grit and finish with PlastiX about every other year before safety inspection. They look like new. The first time it takes a bit more work...but then it only takes a minute or two. I do the same for my other cars.
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74 Targa 3.0, 89 Carrera, 04 Cayenne Turbo
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