I put a Dynomax super turbo on mine in October. Not really loud but a little deeper than stock, no highway drone. Certainly nothing like the Flowmaster 2 chamber dual system I had on my 5.4L F-150. If you want loud I'd look more along those lines. Of course it won't sound like your Shelby till you stuff a Coyote in it, which I highly advise.
There are videos on u tube for various exhaust systems.
2006 Rubi LJ, 6 spd. OME 2.5" HD spring lift, 1.25" JKS BL, MML, discos, front & rear track bars, ZJ steering links, lots of LEDs, Shittybuilt front & rear bumpers, Novak transfer case cable.....blah blah blah