if the pipe was on when the pic on your page was taken, then it doesn't come out far enough to avoid being blown up under the fender, needs to dump outside the trucks air flow .... the problem prolly would go away if the pipe came out behind the truck instead of at the side - I doubt a catylic converter would make much difference in emissions, and wouldn't change the smell problem - certainly not enough to be worth wasting more of the planets limited supply of platinum [over $800/ounce!] on a system not designed to make proper use of it

Bill