Actually your noyt that limited with the roush, the system you want may just take minor fab in the axleback section, all else is bolt on like a stock GT. As for a X or H pipe to work with your current roush system there are tones of options out there. I am leaning toward Pypes X Pipe and Mid Muffler system. If you go to youtube and type in pypes mid muffler system you will see a grabber yellow Stage 2 that sounds really good. i would place a link but works IT system cut out youtube.