A different front pipe.
Return line for the fuel tank.
Ideally a sending unit from a diesel so you have the low fuel waring light (not required though)
A good filter (like a Racor)
A diesel ignition switch that has the preheat position or else a separate momentary switch to do the preheat.
Throttle linkage. This can be a stock one or you can rig a cable actuated one from your existing linkage. The diesel injection pump is on the right side of the engine.
An overdrive
