if its worth it to you to keep the truck, bolt on the 4.0. the trans would be little fab. If you do decide to do this allison makes a killer trans for that motor.
and 4 wheele parts got sum killer headers to help you move mountains, with 50 state legality.
JBA Cat4ward® Headers are the perfect upgrade for todays emissions controlled cars, trucks and SUVs. Engineered with heavy duty features and patented technology, these headers deliver serious performance gains without compromising your vehicles emissions equipment. Bolting on a set of precision made JBA Cat4ward® Headers increases your engines breathing ability and overall efficiency. The result is a significant increase in horsepower and torque throughout the RPM range. You will also improve the throttle response and in some cases your vehicles fuel economy