I almost went upgrade

I also thought of upgrading my eng. My 99GT has high mileage (100,000). If u go with a 5.0 motor, i think u lose your computer monitoring system and u have to upgrade other components. Myself ive decided to go with a new 4.6 motor with a supercharger. That way my on board computer will still read the new engine and keep monitoring the motor and its applicable systems. If u like major muscle , then go for the 5.0 motors. Im staying with the 4.6, light weight and can output tremendous amount of power.