[MARKDTN]

For a stock bottom end GM Tuned Port is great. I know you said a stock manifold (so a TBI type system) but changing the manifold is no big deal. The advantage to this is parts availability at any auto parts store. Dealers that can work on it if necessary. TPI has great low-end torque. TPI does not like high RPM or big displacement. All of these are not issues for a stock truck application. I have done a '72 and 2 square bodies and all are still running and happy. Just a thought.