7.3 is a viable way to go. Budget constraints will put the Kabash on the project because the expense of the adaptation has gone sky high. Valving on these things was and is very restrictive. Open them up and utilize the stock manifold with whatever carb is selected. This alone will bring life to the motor. Want a bit more useable punch? Turbo! He has a good exhaust system that will work. These things were designed primarily to work at 1500 rpm's all day long, and were put into service in big dump trucks to move big loads of dirt around job sites at low rpm. Get it to breathe, and even with the stock camshaft, it will come alive.