I just had a set of flowmaster 40 series mufflers put on my 2008 GT. Then just for kicks I browsed the flowmaster website and got a bit concerned. The only mufflers I saw specifically advertised for the 2005 and up mustangs were those direct bolt on expensive jobs with the tips and curved inlet pipe already on. That is not what the guy put on my car. He put on a set of the original 40 series. It looks like to get them on he just cut the stock pipes flush where they entered the stock mufflers. It appears he then cut the inlet tube off flush off the flows and just welded them on to the stock pipes. He cut my stock tips off and welded them on to the flows. It looks good and sounds great but i just wanted to make sure that set up will work fine and not give me any trouble. There is no way I could have afforded those direct bolt on jobs.