I put a rear spoiler on my 2000 V6. It is carbon fiber and already painted "exactly" to match my car. It looks identical to the GT. Very light weight.
I bought it and had it installed by the dealer when the car was new. I watched the install and I was shocked

, they glued it on!! No kidding! Being just a little concerned with what I saw, I talked to the spoiler dealer installer and they said, because it was carbon fiber and very very light it is made more for looks and does not need to be bolted on. I have had it on the car for 2 1/2 years with no problems. The paint still matches perfectly also.
The price installed was only around $200 and like I said, it came painted.
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-1998 Black Cobra, Kenne Bell 2.1L Supercharged
-2005 Mustang GT, Premium, 5spd, Redfire, Mac Catback
-2007 Roush Nitemare Stage 3 Supercharged #48 of 100