Some ideas:
-- Go roller on the valve train, lifters and rockers (trunnions AND tips).
-- Use very tight tolerances on bearings so lighter oil can be used (5W30).
-- Keep the cylinder tolerances tight so the piston & rings seal in the air/fuel mixture better.
-- Light high-quality components pay off wherever possible, e.g. aluminum heads
-- Get the curb weight of the truck down however possible.
-- Use high-quality headers and catalytic converters.
Those are just a few ideas off the top of my head.
