The rear wings on 99+ Stangs have had different configurations with the posts – none, one, two, and three. What is the story on the posts?
A. The rear wings are a result of Ford factory changes. Roush has basically one wing. The factory mounting points changed from 1999 model to 2000 model. As a result, the factory Mustang wing mounting points were left in the decklid. Rather than fill those holes with rubber grommets, Roush added the extra stantions and found that not only did it give it a distinguished look, but it also filled the holes and provided additional support. Currently, all combinations are available in the Roush catalog. The SM99-1530-AA is a three post wing (or a five post if you add the pedestals.) and the SM01-1530-AA is a two post wing (or a four post wing if you add the pedestals.) So you can get a 2,3,4,or 5 post wing. Whatever one you like is available.