I know its not the 16633. That one is definitely for the N/A which is what I have on my car. I don't know if someone could make a reducer for you at a muffler shop? Personally I wouldn't do that. I'd suggest going on Magnaflow's web site to see if they make one for the SRT. Hopefully someone with an SRT that has an afternarket exhaust will chime in and help you out. I think Borla made an exhaust for the SRT???

Ok I just checked Maganflow's web site for you and they do not offer a cat back or anything for that matter for the SRT. Try Ebay?