I was having some fun just laying under my v-6 last night (and yeah, HAD to put it up on ramps to do it, but it was done)... and there may be something else happening here. If you have Cobra exhaust, that's dual exhaust.... but your v-6 may not be able to be a true dual system. Does your car have one cat. or two? My car, luckily, has true dual capabilities, and it doesn't join until like where the driver's seat is. Now..... You might want to just take a look under your car. If there's only one pipe like all the way back, you'll need an adapter that basically cuts your one exhaust tube (after the cat) into two. This means your Cobra exhaust will have to be cut in half. If your car has two cats, then putting the duals on yourself is rather easy. Welding would be best, but using exhaust clamps is always an option. If it has two cats, measure how long your Cobra exhaust is, and then measure that back to your car, and make a mark on your exhaust tubing like 3-4'' shorter than that. Then, cut along that mark, and try to make it pretty like. Maybe try to get it to fit. It shouldn't be too hard of a set-up. We have the same basic car.... the exhaust my be different however. I don't know why a muffler shop would tell you it's hard... when I"m going to do all my own exhaust, and I'm not a muffler shop, and I don't have the Mustang exhaust like you do. I'm basically going to just build it, lol. If that doesn't work, my car's gonna be quite loud until I can get a kit ordered, lol.