Best thing for a 6…
-Catted H pipe
-Stock GT Catback with Flowmaster Delta 40’s welded in.
Best bet for a 6 cylinder to not sound ricey. Avoid straight through mufflers (Magnaflow, Borla, SLP, etc), and X pipes. Those will cause the rice sound. It’s never going to sound like an 8, but like I said, this is your best bet.