I did the same with the muffler dynomax uses for their rock krawler system. I got the muffler part # from looking at their cat back krawler system and ordered from summit. Welded it up and bought a turn down at the local parts store.

 

Not sure why that first pic is in there, but I also painted everything black with high temp engine paint. Said and done, cost about $75 and sounds and works just as good as the bought system.

FYI: I had a buddy who had the Gibson dual tip exhaust. I watched him back off of a ledge and the tips dug in to the ground and bent and ripped the entire system all the way to the cat. IMO, if you wheel your jeep. I would not go with a dual tip.

 

I have Gibson headers and cat back exhaust. Love the sounds and love the little bit of power gains that I "felt" lol. All I can say though is I live 60 north of NYC and deff happy I bought the stainless steal set. Good luck!

 

Don't pay the price for them. Too expensive. Had the gibson's and lasted 3 yrs and rotted out. Love the sound and style so when I replaced it i went with a camaro storm muffler. The same muffler put 1/2 the price

 

i got my gibson stainless version this summer and it was too drony and raspy at first. then i cut out the resonator and clamped in a test pipe in its place and that was a huge mistake. lost all low end torque, sounded like hell, and engine braking was gone. so i went to pep boys and picked up a vibrant resonator which i got welded in at the local muffler shop.. wow so much better! I love the sound and there is zero drone, no rasp, no putters, not too loud, and when I'm wheeling i just take off the tips.
gibson muffler + vibrant resonator = perfect match! they should sell it as a packaged deal.