I have a 08 Titan SE and my stock muffler is a dual inlet, single outlet muffler. When searching for an aftermarket muffler do I have to find one that is also dual in, single out, or can I get any configuration I want and then have a muffler shop modify the exhaust to fit the new muffler? I would love to know what muffler other's have gone with so I can start looking for 1 to go on my truck. What are some popular choices for a muffler swap? Thanks.