kill the cat if you want whistle - no effect on MPG, but i would do exhaust and leave the intake stock.
you can put a little box/chip on it to help w/ a little power (65hp or so)
the weak link in the 6.0 is the head bolts/headgaskets(cause of the 'puking' problem w/ the coolant you might have read about), but if you dont chip it 2 hot you wont really have any issues with them. the other weak link is the egr (the fact that it is there) - do yourself a favour and unplug it. other than that you should be good to go!
welcome to SDD, and i hope you love the 6.0!
you can put a little box/chip on it to help w/ a little power (65hp or so)
the weak link in the 6.0 is the head bolts/headgaskets(cause of the 'puking' problem w/ the coolant you might have read about), but if you dont chip it 2 hot you wont really have any issues with them. the other weak link is the egr (the fact that it is there) - do yourself a favour and unplug it. other than that you should be good to go!
welcome to SDD, and i hope you love the 6.0!