Doing something different is what created that problem... Do it like the factory engineers designed.
See the CO detector next to the radio? That is there because I had a bad case of CO poisoning caused by a leak that let a whole lot less CO into the cab than what you have.That's just one reason not to dump the exhaust before the factory did. The other is that CO can collect underneath your Jeep and depending on conditions, it could make its way up into the passenger compartment. I'd have it extended out so it's at or close to where the factory put it.