Hey
Yeah, I have a 40 series flowmaster. It is a TIGHT fit, but it did stuff in there. I had to remove most of my heat shield. (I was a little worried about this, but so far nothing has melted inside my car :D) And, I have gone on several 200 + mile road trips with it, not to mention I drive for work every day, and havent noticed any increase in cabin temp.
Oh yeah, and i have it where the resonator was. Like I said, it is a tight fit, but it worked.
Good luck on whatever you choose.
