hey i find that if you cut your exhaust off at the caddi and use flex hose and run it out the side of the jeep in front of the back tire it kills that smell automatically and you wont smell like gas or exhaust fumes
i no what you mean by exhaust smell in the cockpit i have a 88' jeep cherokee sport and the exhaust will drive you out my sollution to that problem was i cut the exhaust off at the catti and put flex hose out in front of the rear tire and that killed the smell